jump to navigation

What is a “Use Case”? How is Use Case Modeling used to manage software development projects? June 28, 2009

Posted by HubTechInsider in Project Management.
Tags: , , , , , , , ,
2 comments

The History of Use Case Modeling

A gentleman by the name of Ivar Jacobson invented what later has become known as Use Cases while working on telephony systems at Ericsson in the late 1960s. In the later 1980s, he introduced them to the OOP, or Object Oriented Programming, community. Within that community, Use Cases were instantly recognized as filling an important gap in the requirements process.

Alistair Cockburn (pronounced “Coburn”) constructed the Actors and Goals conceptual model while writing Use Case guides for the IBM Consulting Group in 1994, after studying under Ivar Jacobson in the early 1990s. Cockburn’s Actors and Goals conceptual model help to resolve much of the mystery of Use Cases and provided a guide on how to write and structure Use Cases. I was exposed to Jacobson and Cockburn’s Use Case modeling concepts while working as a consultant and business analyst for IBM in the 1990s. Cockburn’s IBM Consulting Group Actors and Goals conceptual model has circulated informally since 1995 at http://alistair.cockburn.us/ and later at http://www.usecases.org. The ideas finally were published in the Journal of Object Oriented Programming in 1997, in an article I read and loved written by Alistair Cockburn entitled “Structuring Use Cases with Goals“.

From the early 1990s through the end of the dotcom Boom around 1999, the ideas remained static, even though many in the OOP community still felt that there were some underlying loose ends in the theories behind Use Case Modeling. Alistair Cockburn, the originator of so many of the Use Case Modeling conceptual underpinnings, continued to teach and coach his Actors and Goals model, eventually gaining insights into why many in the OOP community were having such a hard time coming to grips with the ideas being presented. He finally released his new insights, complete with some of his resolutions to the unresolved questions forwarded to him regarding the Actors and Goals model, as the Stakeholders and Interests Model.

UML and Use Case Modeling: differences and coexistence

I personally, when introducing these concepts to a new Project Team, have often been asked, “What impact or overlap is there between the Use Case Modeling ideas and UML, or the Unified Modeling Language”?

A former colleague of Jacobson’s, Gunnar Overgaard, wrote most of the UML use case material and worked to preserve the heritage of Jacobson’s ideas. But it is well known within the OOP community that the UML standards group has within it a strong drawing-tools influence, which results in the loss of much of the textual, prose-based nature of Use Case Modeling.

Alistair Cockburn has written that he has met with both Gunnar Overgaard and Ivar Jacobson, and both assured him that Use Cases may fit within one of the UML ellipses,and hence the UML standard is agnostic when it comes to the Use Case Modeling ideas. The ideas forwarded by Alistair Cockburn are fully compatible with the UML 1.3 use case standard.

I think it is very important, however, to realize that if you only were to read the UML standard, which does not discuss the content or writing of a Use Case, you will not understand what a Use Case is or how to write or use it, and you will be led in the dangerous direction of thinking hat Use Cases are a graphical, as opposed to a textual, or prose, construct.

What is a “Use Case”, and how is Use Case Modeling used?

A Use Case is a fundamentally prose text description of a system’s behavior under various conditions. These conditions are primarily responses of the system to requests from one of the stakeholders of the system in question, usually referred to as a “Primary Actor”.

A Use Case represents a type of contract between the stakeholders of a system about the behavior of that system under these various conditions, or “States”. The Primary Actor initiates an action with the system in order to accomplish a task or achieve a goal. Myriad scenarios can unfold subsequently, and those scenarios depend upon the type of interactions or requests made by the Primary Actor and the conditions or states which accompany those requests. The use case succinctly codifies these various scenarios together into a presentable format.

Although use cases can take the form of flow charts, “Petri nets”, sequence charts or even programming languages, they are usually (and through general practice and agreement, best) presented in a prose text format. They are a way to communicate the intended behavior of a system (many times of course a software system) amongst members of a project team. It should not be necessary for project team members to have special training in order to interpret a well written use case. Use cases serve to encourage communication between project team members and also to stimulate discussion around contention points of a system’s intended behavior.

Some project teams may choose to document the requirements of a software system only through the use cases themselves. Other project teams may choose to have separate, traditional requirements documents. Many project teams may choose to provide both forms of documentation, use cases and requirements documents. I am of the school that use cases, requirements documents, and test cases form a triad that can help to unequivocally clarify the intended behavior of even the most complex software systems and also give the testing team the very best chance to perform their job with precision and efficiency.

The same basic rules of writing apply to all of the above listed approaches, even though different project teams will choose to write with unique levels of technical detail and completeness of description.

A well written use case should be easy to read and consists of sentences that are succinct and written in only one grammatical format, that being a simple action step. An action step is defined as an event in which one actor achieves a result or passes information or results to another system actor. An actor is defined as anyone or anything with behavior.

Reading a use case should not take more than a few minutes, although learning how to write a good use case is considerably harder. Three fundamental concepts apply to the writing of use cases, all three of which need to be mastered in order to become an effective use case writer:

  1. Scope: What is the system being discussed, and what are the boundaries of the actions within that system to be described?
  2. Primary Actor: Who is the user who hopes to achieve a goal through interaction with the system in question?
  3. Level: Is the goal trying to be achieved by the Primary Actor primarily a high level goal or a low level goal?

The components of a use case consist of the following:

Stakeholder:  someone with an interest at stake in the proper behavior of the system under discussion.

Preconditions and Guarantees:  States or conditions that must be true both before and after the execution of the sequenced steps in the use case.

Main success scenario: A use case scenario in which no deviations from the expected behavior of the system are encountered.

Extensions:  Extensions describe alternate scenarios or states that can be encountered during the execution of a use case. Numbering convention used in the writing of a use case indicate to the reader points at which deviations from the main success scenario are possible. For example, steps 2a and 2b are indicative of twin conditions that can be arrived at by the primary actor during the execution of step 2.

How can Use Case Modeling assist Project Managers in managing complex software development projects?

Use cases provide a scaffolding construct that can be used by Project Managers or Program Managers to link many of the requirements details used on a modern software development project. Information contained within different parts of the software requirements definition (SRD) such as user profile information, data formating requirements, validations, and business rules can be cross linked and cross referenced through the utilization of Use Case Modeling.

In addition to this linking of requirements for a software development project, Use Cases and Use Case Modeling can help structure the project planning process by providing a framework upon which to hang information such as development status, release dates, teams, and priorities. The project team can employ Use Cases to track results, in particular the design of the User Interface components and system tests. It is for these benefits that many people seem to consider Use Cases as at the center or hub of a giant wheel of requirements consisting of spokes for performance requirements, UI requirements, UI design, business rules, data formats, input / output protocols, and performance requirements. Use Cases are often thought of in the OOP community as being the central element of the requirements or even the central element of the software development project’s development process.

At what points in a software development project do Use Cases add value?

Use Case modeling has garnered such a popular and ardent following within the OOP community precisely because Use Cases have the ability to tell coherent stories about how the System under discussion will behave in use. The end Users of the System get to see just what this new System will be and what functionality it will possess. They have the option to react early or fine tune or reject the User Stories implied in the Use Cases themselves (“You mean we’ll have to do what in order to cancel an Order?”). As important as this reason is to the widespread adoption of Use Case Modeling, this is only one of the ways in which Use Cases can contribute value to a software development project, and quite possibly not the most significant.

The very first moment during the course of a typical software development project that the Use Cases create value is upon the naming of these Use Cases as the User Goals that the System will support. These User Goals, in the form of the collected and named Use Case Catalog, form a list which announces what the System will do, revealing the scope of the System, its purpose. The list of named User Goals becomes a communication device between the different Stakeholders on the software development project.

The list of User Goals will be reviewed and debated upon by user representatives, software development engineers, executives, and project managers, who will use this list to estimate the cost and complexity of the System by using it as a guide to the functionality under construction. The list of User Goals will be used to negotiate which functions will be built first and how the teams are to be set up. The User Goal list is a framework upon which complexity, status, cost and timing metrics may be hung. It collects diverse and myriad project information over the course of the life of a software development project.

Why you should perservere through the writing of the Use Case failure conditions

The second instance where Use Case Modeling adds value during the course of a software development project is when the people or person writing the Use Cases brainstorm all the things that could go wrong in the MSS (Main Success Scenario). When the Use Case writers list out all the failure conditions, and how the System under discussion will handle these error or failure conditions, this is the point in the process where the Project Team is likely to uncover something surprising, maybe even something that nobody, including the Use Case writers themselves or the primary stakeholders, ever thought about as requirements.

The writing of the Use Case failure conditions is probably one of the most simultaneously frustrating and rewarding steps in the process of writing the Use Cases. I highly encourage everyone ever involved in writing of a catalog of Use Cases to hold out until this part of the process.  It is during the writing of the extensions, or failure conditions, that I regularly uncover a new User Goal, primary or secondary stakeholder, business rule or business process. Some of the most collaborative and productive design review sessions have resulted from discussions surrounding topics of how to handle these failure conditions. These design review sessions frequently end up involving a group of SMEs, or Subject Matter Experts, reviewing business processes or even questioning why it is things have been done a certain way inside a particular organization for so long. The process of trying to resolve what the System’s behavior should be during failure condition scenarios oftentimes is the process that generates the best requirements, even ex post facto to the formal discovery process.

If your Project Team skips over the writing of the Use Case failure conditions, then you will miss a valuable opportunity to catch many of the error conditions of the software application your Team is designing, leaving this vital Project task to a programmer who may discover them while typing a fragement of computer software code. This is far from the ideal juncture of your software development Project to be discovering new functions and business rules. If a lone programmer is left to his or her own devices in this type of scenario, with the business experts probably not around or gone home for the day, time pressure mounting, delivery schedules slipping, a programmer may be pressed, and understandably so, to just type whatever they think up at the moment instead of determining the correct functional behavior for the System they are programming, not necessarily designing.

I encourage Project Team to at least draw up one or two paragraph Use Case Briefs — for the very simple reason that Project Teams who write one-paragraph Use Cases save a lot of time by writing so little and already reap one of the major benefits of Use Cases. Project Teams who perservere through failure handling save mountains of time by finding subtle requirements early.


Subscribe to HubTechInsider on YouTube

PHP for Beginners

Google+ Domination Video Training Course

LinkedIn for Business Training Course


Want to know more?

You’re reading Boston’s Hub Tech Insider, a blog stuffed with years of articles about Boston technology startups and venture capital-backed companies, software development, Agile project management, managing software teams, designing web-based business applications, running successful software development projects, ecommerce and telecommunications.

About the author.

I’m Paul Seibert, Editor of Boston’s Hub Tech Insider, a Boston focused technology blog. You can connect with me on LinkedIn, follow me on Twitter, even friend me on Facebook if you’re cool. I own and am trying to sell a dual-zoned, residential & commercial Office Building in Natick, MA. I have a background in entrepreneurship, ecommerce, telecommunications and software development, I’m the Director, Technical Projects at eSpendWise, I’m a serial entrepreneur and the co-founder of Tshirtnow.net.

What is the “n body problem”, and what does it mean for software project management? June 23, 2009

Posted by HubTechInsider in Project Management.
Tags: , , , , ,
add a comment

It can be shown that for n project team members, there are [ n (n-1) / 2 ] possible working relationships. These working relationships grow with increased project team size as the aforementioned polynomial function shows. Of course, any of these working relationships are in danger of deteriorating, and the ones that are working out great are not necessarily transitive. For example, just because Tom and Wendy work great together, and Wendy and Susan work well together, it does not follow that Tom and Susan will work well together.

Further complicating these working relationships are externalities such as intercultural differences and outsourcing of project resources and pieces of the project work.

As bluesman Robert Cray would say: “Too many cooks are gonna spoil the stew” – or, as Fred Brooks of The Mythical Man Month has said in the central thesis of this classic software development text: “adding manpower to a late software project makes it later”.

The above factors are important to consider as a Project Manager. Poor team chemistry can ruin your chances to overcome the traditional project constraints of time, budget and resources even if your project team has at its disposal high quality technical talent.

The success of your project depends on both the quality of the talent on your project team and the manner in which that talent is engaged on your project.

It is currently fashionable for employers to surmise that a project’s success is only dependent upon the technical skill of the project team members. This is far from the truth, although a pleasant fiction for human resources and senior management.

As a Project Manager, you need to possess a wide range of people skills including team building, negotiation techniques and natural affability, you must be a master communicator, you must understand human behavior and team building and dynamics, you must be a great motivator and have innate knowledge of how to create and enhance esprit de corps.

Even the most highly technical situations are governed by human relationships and human nature. Your technical abilities and credibility as a technician carries weight with management and your project team members, certainly, but it is not your primary purpose as a Project Manager to serve as a technical resource, and all the technical skill in the world won’t save you if you can’t “Herd cats”.

The special challenges of software development will  rear their ugly heads in the midst of this, imposing their will upon the challenges of management of human teams. Only a skilled team, skillfully managed, can achieve success in most software development project situations.

“Good bow, hard to bend. Good horse, hard to ride. Good man, difficult to lead well”


Want to know more?

You’re reading Boston’s Hub Tech Insider, a blog stuffed with years of articles about Boston technology startups and venture capital-backed companies, software development, Agile project management, managing software teams, designing web-based business applications, running successful software development projects, ecommerce and telecommunications.

About the author.

I’m Paul Seibert, Editor of Boston’s Hub Tech Insider, a Boston focused technology blog. You can connect with me on LinkedIn, follow me on Twitter, even friend me on Facebook if you’re cool. I own and am trying to sell a dual-zoned, residential & commercial Office Building in Natick, MA. I have a background in entrepreneurship, ecommerce, telecommunications and software development, I’m the Director, Technical Projects at eSpendWise, I’m a serial entrepreneur and the co-founder of Tshirtnow.net.

Eight ways to tell if your project team is on the way up or on the way down June 21, 2009

Posted by HubTechInsider in Project Management, Uncategorized.
Tags: , , ,
2 comments

In my professional roles leading software development teams, I have found that how Project Managers interact with their project team says not only alot about them as leaders, but also speaks volumes about the state of the organization itself. There is a dynamic lifeblood of personal relationships and interactions at the heart of a software development team that is an interesting take on leadership and team behavior. Your project team is either on the way up, or it is on the way down. In like fashion, your organization is either on the way up, or it is on the way down. Not every sign is easily recognizable at the time for what it really represents in terms of the direction your project team is heading.

 

A project team and an organization’s decline is like a disease: it is harder to detect but easier to cure in the early stages, and easier to detect but harder to cure in the later stages. Your project team and the encompassing organization may appear to be strong on the outside, but savvy insiders may be able to comprehend that your team is on the cusp of a dangerous and fatal fall off the cliff.

 

I have had the benefit (as I view it; Some would say curse) of having watched project teams in several different organizations and multiple industries. But it was easy to write about the below eight indicators because the signs tend to be the same regardless of the company and industry. In my role, you need to foster the good kind of environment where your project team can feel that the individuals are gelled into a cohesive unit that is winning. This feeling, rarely experienced, is like magic, and when a project team is hitting on all cylinders, each individual is capable of contributing their best to the endeavor at hand and feels like they are part of something special. Do your best as a Project Manager or team leader to foster this type of environment. Watch closely the eight key performance indicators I write about below and see how your current (or past) project teams have reflected which direction they are / were traveling in. You are either on the way up, or you are on the way down.

 

1. How is reality faced? – A team on the way down will shield the business owner or project sponsor from unpleasant facts – fearful and trepidacious, expecting criticism and penalties as a result of exposing rough realities. A team on the way up will constantly be exposing harsh realities: “Hey, man, look at this — this sucks hard…we got to fix this, and now”. Team members of a team on the way up will always bring forth these types of facts, as their project manager / team leader will never be critical of those who bring these ugly facts to life, feeling they need to be discussed and rectified.

 

2. How do project team members assert and support their opinions? – In a team on the way down, project team members will assert their opinions strongly, but will not provide data or evidence needed to form a strong and compelling argument. In a team on the way up, team members readily offer up solid data, evidence and bring logical argumentation skills to the discussion.

 

3. What style does the Project Manager use? – If the Project Manager or Project team leader uses a very low questions-to-statements ratio, and avoids critical input and allows sloppy reasoning and unsupported personal opinions to circulate in meetings, then your team is probably on the way down. However, if your PM or leader employs a Socratic style, using a high questions-to-statements ratio, challenges people and pushes for penetrating insights, then your team is probably on the way up.

 

4. How does the team coalesce behind decisions? – If team members grudgingly acquiesce to a decision but do not unify behind it or even work behind the scenes to undermine the decision ex post facto, then your team is on the way down. Teams on the way up will unify behind a decision once it is made, and work to make it successful, even if they did not initially agree with it.

 

5. How does the team give credit to each other? – Teams on the way down will seek as much credit for their own part of the job as possible for themselves, often not even noticing that this style seldom results in the confidence and admiration of their peers. In a team on the way up, project team members will credit others for success, and they find that this tendency will result in the admiration of and confidence from the other project team members.

 

6. Do team members need to look smart in front of each other? – In a team on the way up, project team members will argue to look smart or to further their own particular interests within the organization, but in a team on the way up, team members’ arguments and debates are all geared towards finding the very best answers to the problems and issues the project team is facing. Nobody worries about “Looking smart” in a team on the way up, because they have internalized that old saying: “Being smart’s alot like being ladylike: if you have to say you are, you probably aren’t”. Nobody in the team on the way up wants to look cool – they want to be cool.

 

7. Does the team conduct ‘post-mortems’, and how? – In a project team on the way down, culprits are sought for blame rather than in a team on the way up, where autoposies are conducted in order to mine wisdom and learning for the next time around or to make sure that the misstep results in a learning experience. Otherwise, a mistake is a mistake made twice. Project teams on the way up don’t have time to blame team members – they are too busy moving forward with the next items of business.

 

8. How about results? – Teams on the way down, unsurprisingly, often fail to deliver great or even good results. They spend alot of time blaming either individual team members or outside factors for setbacks and failures. A team on the way up, in contrast, is comprised of individual team members who are all delivering exceptional results, but in the case of mistakes, setbacks, and errors, each team member accepts full responsibility on their own and learns from the mistakes. The project team on the way up fosters this environment which enables each individual team member to feel comfortable doing so.





Want to know more?

You’re reading Boston’s Hub Tech Insider, a blog stuffed with years of articles about Boston technology startups and venture capital-backed companies, software development, Agile project management, managing software teams, designing web-based business applications, running successful software development projects, ecommerce and telecommunications.





About the author.

I’m Paul Seibert, Editor of Boston’s Hub Tech Insider, a Boston focused technology blog. You can connect with me on LinkedIn, follow me on Twitter, even friend me on Facebook if you’re cool. I have a background in entrepreneurship, ecommerce, telecommunications and software development, I’m the Senior Technical Project Manager at eSpendWise, I’m a serial entrepreneur and the co-founder of Tshirtnow.net.


Add to FacebookAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to TwitterAdd to TechnoratiAdd to Yahoo BuzzAdd to Newsvine

Five tips for recruiters on contacting potential job candidates in a tough job market June 15, 2009

Posted by HubTechInsider in Staffing & Recruiting, Uncategorized.
Tags: , ,
4 comments

I have been on both sides of the fence when it comes to job interviews — for the two ecommerce software companies I started back in the 1990’s, I hired hundreds of people, so I talked to alot of staffing firms and recruiters. In my current life as an IT Project Manager / Business Analyst / Program Manager, I have not only taken on a few contract roles in the Boston area myself, but I have also been tasked at various times with hiring other contractors to work on large software development projects. In all these roles, I have been in contact with staffing firms, agencies, and corporate recruiters that are not very good at their job. Many of the recruiters out there are great, but the majority are not great. After reading yet another drivel and platitude filled article about recruiters and “how to get a job” from the Boston Globe today, I thought it was high time for an article with some real-world tips and practical advice for recruiters on how to contact candidates out there in the midst of a tough job market. I found after writing these five tips for recruiters, however, that they are applicable in any economy. These five tips are fundamental imperatives for all recruiters to read, know and internalize so that they do not destroy their professional reputations and ruin the reputations of their staffing firms and employment agencies.

1. Do your homework on candidates before picking up the telephone – If you don’t have any jobs for a candidate, don’t call them up on the telephone. If a candidate is not a good fit for your particular search, then they are not going to be interested in hearing from you: think about it. Just because someone is a candidate and is out there looking for work, doesn’t mean they are going to be thrilled to talk to a recruiter on the telephone. They will really be perturbed at you when they realize that after an initial contact, you didn’t look at their resume or their Linkedin profile or really perform any homework on them until you get them on the telephone – only to tell them they aren’t a good fit, not what you’re looking for or you don’t have any jobs for them. You should have never called them on the telephone in the first place. Lazy recruiters are all too common these days, and nobody wants to hear whining about time constraints, number of candidates, or the rest of it. Get on LinkedIn, read the profiles of your candidates, and carefully read their resume. In this way, you can be ready to ask purposeful leading questions such as “So I read about your experiences with the Executive Dashboard application at Metatech; I know you wrote on your resume that it was an Oracle project, but I’m wondering if that was a .net or a J2EE environment. Can you tell me a little more about it?”… this is a great way to get the information you need from a candidate and it prevents you from looking like a brainless recruitron. If you are a recruiter and you are not on Linkedin yourself, the message you are sending out is that you are not a veteran, serious, professional recruiter, and you are, in fact, recruiter that has something to hide and should not be trusted. When you do get a potential candidate on the telephone, announce yourself with politeness: “Hi, this is Wendy Sprague from Recruit-Tech, and I’d like to speak with Susan Holmes if she is there please” is a great way to reach Susan about a potential job opportunity. “Hi, is this Susan?” is an example of a bad way to begin such a sourcing call. Be polite on the telephone! Do your homework on the candidates!

2. Don’t be rude on the telephone with potential candidates – The internet is a two-way street. In other words, people can write about you and your company / staffing agency / firm online. And they will. I started a few ecommerce companies in college. I used to tell my employees: “If someone has a great ordering or retail experience with us, they will tell two of their best friends – if they have a bad experience they will tell ten or fifteen people right away”. Not doing your homework on candidates before getting them on the telephone, wasting their time on the telephone, rudeness, insulting people’s backgrounds or resumes because they aren’t the pink unicorn you are currently searching for, cutting people off, telling them they “aren’t the right fit” when you should have been able to tell that before calling them up, etc. is going to work out badly for you in the long run. A candidate is just one person. A company is exposed to the public and a corporate reputation for rudeness and incompetence is alot harder to overcome than a single, individual’s reputation. In essence, a staffing firm is a very visible public entity and word gets around. Don’t forget: contractors talk to each other and to the clients once they are in the client company. Many are eventually hired permanently and even ones who remain contractors are often tasked with hiring other contractors. Remember this the next time you are speaking on the telephone with a candidate, because they will surely remember you.

3. Your candidates’ professional references are not marketing contacts – A typical ploy in the tough current Boston IT contract market is to call in job candidates for an in-person interview on the pretext of some nonexistent job or some vaguely-defined future contract. Then, in this challenging market for staffing firms, the account managers are tasked with getting the candidates to “Drop the cheese” and the candidate is then grilled for marketing information for the staffing agency or firm. Manager’s names at former employers, managers at the current employer, etc. are all gathered. Then, a bogus in-person “reference check” is set up. The staffing firm then essentially “calls in” the favor of an in-person reference check using the candidate’s name – to try and drum up new business for the staffing firm at the candidate’s former or current employer. Your candidate’s professional references are not marketing material for your staffing firm. What is likely to happen is the manager will call up or email the candidate and tell them about this marketing meeting, and that staffing firm will never get any future business from the candidate’s former employer. Again, people talk in this new age of social media and online blog posts. So don’t do it. Your candidate’s professional references and work history is not an opportunity for your staffing firm to “get in the door”. If you use these disingenuous methods, it will be exposed in public and also behind closed doors at the offices of your potential clients – not to mention all the contractors and potential candidates that will turn up their noses in disgust at the infinite re-telling of the story. Staffing firms have alot of competition, and there are so many other firms to go with — don’t accept this high level of business risk.

4. Don’t wear out your candidates’ professional references – Get the candidates professional references and then ask the permission of the candidate to call them. Don’t call them before you have a definite REQ for the candidate and they are indeed a primary candidate for the job. The reason for this is simple: professional references are usually busy people and it is not their job to give detailed references for former employees. It is a difficult and tense thing for managers to do even for people and former employees who were superstars and well liked. Most managers will give a candidate one or two really good references, but by the time they are called for a third or fourth reference, they are either not giving them or not giving good ones anymore. So don’t wear out the professional references of your candidates! Again, this is another point of which I must emphasize that word gets around – quickly in this world of blogs, twitter, and such.

5. Have integrity and follow-through – If you only have one job REQ (or no REQ) for a candidate, if you tell them your firm has lots of potential jobs for their title and role, which you don’t follow up on with the candidate, they will tell everyone they know that you and your staffing agency / firm lied to them. Eventually, they will get hired, but they won’t ever forget that you lied to them – why place an enemy in so many potential client firms? In matters of personal livelihood, people in general have long memories. So don’t think they forgot about all the jobs for them you told them about. To come and meet with you in your office, most candidates will have to use up a sick day or miss a day of work. So you better get down to business with your candidates quickly. To lie about these types of matters is not harmless to the job candidate, and it’s not harmless to the business of the staffing firm or agency, let alone your personal professional reputation. Again, don’t do it.

A good article I found online that makes some great points about hiring in a down economy is available here, and I recommend it highly.

Add to FacebookAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to TwitterAdd to TechnoratiAdd to Yahoo BuzzAdd to Newsvine

What is “management by walking around”? June 13, 2009

Posted by HubTechInsider in Agile Software Development, Management, Project Management, Uncategorized.
Tags: , , , , ,
4 comments

Sometimes also called “Management by walking around” or MBWA, management by sight is a management strategy that can and should be integrated into any management style or approach. It is very people-oriented and it requires managers to be visible and interact heavily with project team members. Interactions at all levels of the project team foster the quick and efficient gathering of information about the project and the project team members.

Management by sight is very direct and the manager practicing it utilizes observation and visibility to conduct project analysis and project leadership, to monitor the situation, and to provide control when necessary.

I have had a great amount of success using this management technique and I thought I would share with you twelve guidelines for MBWA which were shared with me by @sjohnson717 on Twitter in response to this original MBWA post. These tips are great and I recommend following them when using this very simple and effective management technique.

Simple and effective management techniques are what every manager needs more of these days!

Add to FacebookAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to TwitterAdd to TechnoratiAdd to Yahoo BuzzAdd to Newsvine

 

Want to know more?

You’re reading Boston’s Hub Tech Insider, a blog stuffed with years of articles about Boston technology startups and venture capital-backed companies, software development, Agile project management, managing software teams, designing web-based business applications, running successful software development projects, ecommerce and telecommunications.

About the author.

I’m Paul Seibert, Editor of Boston’s Hub Tech Insider, a Boston focused technology blog. You can connect with me on LinkedIn, follow me on Twitter, even friend me on Facebook if you’re cool. I own and am trying to sell a dual-zoned, residential & commercial Office Building in Natick, MA. I have a background in entrepreneurship, ecommerce, telecommunications and software development, I’m the Director, Technical Projects at eSpendWise, I’m a serial entrepreneur and the co-founder of Tshirtnow.net.

management, mbwa, management by walking around, it management, it, information technology, project management

Pyxis Mobile develops mobile applications for the hot mobile software market from their headquarters in Waltham, MA June 12, 2009

Posted by HubTechInsider in Mobile Software Applications.
Tags: , , , , ,
add a comment

6 billion wireless applications will be downloaded to smartphones by 2014, and Waltham, MA-based Pyxis Mobile is aiming to have a large piece of that market.

The company began selling software for mobile telephones in 2004.

The top picks for development environments in the mobile space seem to be RIM’s Blackberry platform, Microsoft’s Windows Mobile, and Apple’s iPhone platform. RIM leads among business users, having sold 17.5 million Blackberry devices used for business last year, compared with 11.6 million Windows Mobile devices, 9.8 million telephones running Symbian, and 3.9 million iPhones. Google’s Android platform is a new competitor in this space, with several new Android handsets coming onto the market this year.

Pyxis Mobile is concentrating most of its development efforts on the Blackberry platform, but also has versions of its software available for both the iPhone and Windows Mobile.

Twelve Tips for Agile Project Planning and Estimating June 12, 2009

Posted by HubTechInsider in Agile Software Development, Project Management.
Tags: , , , , ,
5 comments

Agile planning differs from the traditional software project management approaches by having as its central purpose the discovery of an iterative, optimal solution to the main product development constraints of what requirements in what timeline and with what resources.

The Agile project planning approach succeeds where more traditional planning and estimating approaches for software development projects have failed in that Agile plans focus on features rather than tasks, re-planning occurs frequently, plans are developed at different levels (portfolio, product, release, iteration, day) and because the size of a project is treated as separate from the duration of the project’s timeline, which is derived from the project team’s velocity through the decided-upon project size. Small numbers of requirements in each iteration of working software keeps work flowing, and work in progress is eliminated at the end of each iteration. Progress of the project team is measured at the team, rather than the individual level and uncertainty is acknowledged as a fact of life and is planned for accordingly.

For all of the above reasons, here are twelve tips for Agile project planning and estimating:

1. Keep everyone on the team involved – Buy-In, or real commitment, from every member of he project team is vital to the success of the project. For example, the estimation of the project is an activity that should involve all members of the project team, while only very particular tasks such as prioritization of requirements should be the primary responsibility of the product owner or an individual project team member. The more work is shared by the team, the more victories the team will have to share.

2. Plan on at least three levels – Release, Iteration and Day. Each of these three plans has a different time horizon with a different level of granularity, and each serves a different purpose in overall project planning. Do not fall into the trap of thinking that an iteration plan is a substitute for a release plan, or vice versa. There are Agile Strategy, Portfolio, Product, Release, Iteration and Day plans. Each project team such plan on at least the Day, Iteration and Release levels consistently.

3. Separate project size and project duration by using different measurement units for each – An effective technique for doing this is to estimate the project’s size in “Story Points”, or arbitrary numerical values assigned to requirements with the agreement of the entire project team and translating the project size into duration using velocity. This has the added benefit of having he project team speak of the seperate concepts by always using different terms of measurement for each when speaking amongst themselves and others outside the project team.

4. Uncertainty should be communicated by using either the date or the iteration’s functionality – Use the primary fixed constraint to express the uncertainty that all well-laid project plans must express in the midst of an uncertain world to express this uncertainty. If the number of software requirements and application functionality to be included in the iteration is fixed, then express your uncertainty as a date range: “We’ll finish in the second quarter” or “We’ll finish in between two and five iterations”. If the iteration release date of the iteration is instead fixed, then express your uncertainty as a range of available application functionality: “We’ll finish by 15 May, and the application will include these requirements, but probably not these requirements implemented as features”. When you have more uncertainty in your project planning, use bigger units (iterations, months, and then fiscal quarters).

5. Plan to replan frequently – If information used to plan the current project plan has now changed, incorporate those changed pieces of information into the current project plan. his will aloow the project plan to adapt and grow in response to changing conditions. This is an oportunity to show why Agile project plans are called Agile in the irst place. Ensure that the project team is always squarely aligned at the goal of delivery the maximum value to the organization.

6. Communicate progress and track progress of the project team – Keep the project’s primary stakeholders infomed of the progress of the project team by regularly publishing simple and easy to understand charts indicating the progress of the project team. Burndown and velocity charts are an excellent way todo this easily and simply.

7. Plan to learn from and adapt to an Agile project –

8. Plan requirements of the correct dimensions –

9. Prioritize requirements well – Work should progress on software requirements in such a manner as to maximize the entire value return of the project.

10. Base your project plans and estimates on reality –

11. Learn to Pad your schedules correctly – A software development team scheduled to within an inch of its life cannot progress efficiently. Do not plan on using 100% of an available resource or individual 100% of their available time. Do not over-schedule. Put some slack into you project plans and prevent project gridlock.

12. Create rolling lookahead plans for the project team’s use – With multiple teams performing work on a project, coordinate their work through the use of rolling lookahead planning. Looking ahead to allocate requirements to specific future iterations and spotting and planning of interteam dependencies is also enabled.


PHP for Beginners


Want to know more?

You’re reading Boston’s Hub Tech Insider, a blog stuffed with years of articles about Boston technology startups and venture capital-backed companies, software development, Agile project management, managing software teams, designing web-based business applications, running successful software development projects, ecommerce and telecommunications.


About the author.

I’m Paul Seibert, Editor of Boston’s Hub Tech Insider, a Boston focused technology blog. You can connect with me on LinkedIn, follow me on Twitter, even friend me on Facebook if you’re cool. I own and am trying to sell a dual-zoned, residential & commercial Office Building in Natick, MA. I have a background in entrepreneurship, ecommerce, telecommunications and software development, I’m the Senior Technical Project Manager at eSpendWise, I’m a serial entrepreneur and the co-founder of Tshirtnow.net.

Add to FacebookAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to TwitterAdd to TechnoratiAdd to Yahoo BuzzAdd to Newsvine

What is Cao’s Law? June 11, 2009

Posted by HubTechInsider in Definitions, Fiber Optics, Telecommunications.
Tags: , ,
add a comment

Cao’s Law states that the communications spectrum is virtually infinite and that WDM (Wave Division Multiplexing) will allow the information transmitted upon the available spectrum to expand exponentially as the growth of transistors in Moore’s Law. Using less and less power, WDM will allow finer and finer channels of light to transmit more and more data. Cao’s Law states that these lambdas will expand at a rate two to three times the rate of expansion of transistors on an integrated circuit chip as in Moore’s Law. On optical fibers, as opposed to the tradeoffs between power and connectivity in the transistor world, in the optical realm, the tradeoff is between bitrate and channel count. To this point of the technology’s development, we can either pump a high bitrate on each channel or we can transmit lots of channels, but we cannot do both of these things at the same time. Among telecom carriers today, there seems to be a manifestation of Simon Cao’s Law in action in the real world.

SS7 – Signaling System Seven – Telecommunications Protocol SS7 June 10, 2009

Posted by HubTechInsider in Fiber Optics, Telecommunications.
Tags: , , , , , , , ,
1 comment so far
SS7 software layers

SS7 software layers

In Signaling System 7 (SS7) protocol, a worldwide standard (with variations), routing intelligence is located in low cost computer-based equipment rather than in central office switches.

One of the primary benefits of SS7 is global interoperability. It has the capability to enable all carriers to cooperate with each other. It is a standard protocol approved by the ITU. Global billing, toll-free calling, 900-number services, and international wireless call roaming are all call features that are dependent on SS7.

SS7 is used on a global basis. In North America, the ANSI version of SS7 is used. In Europe, the ETSI version is used. In other pats of the world, the ITU version of SS7 is used.

Gateways allow these international SS7 implementations to communicate with each other.

SS7 is essential to modern networking. With SS7, an overlaid packet switched network controls the underlying voice network’s operation and signaling information is carried on a separate channel from voice and data traffic.

Because signaling is such a quick network activity, it is possible to multiplex many signaling messages over one signaling channel using a packet switching arrangement.

SS7 permits the telephone company to provide one database for several switches in order to freeup switch capability for other functions. This is the capability that makes SS7 the foundation for Intelligent Networks (INs) as well as Advanced Intelligent Networks (AINs).

As an example, in order to provide a service such as 900 number and toll-free calling, in SS7, powerful parallel processing computer systems hold massive databases with information such as routing instructions for toll-free and 900 number telephone calls. One processor with its database supports many central office switches under SS7. in this way, each central office itself is not required to host the centralized database. Without the need to share the expense of maintaining the sophisticated routing information, each central office can share in the expense of a database or feature upgrade to the centralized SS7 datastore.

MCI first implemented SS7 into its network in 1988. SS7 enabled them to halve their call setup time on calls between Philadelphia and Los Angeles. Freeing up voice channels from their previous signaling duties pre-SS7 enabled carriers to pack more voice calls on their existing network paths.

Cellular networks use SS7 technology to support roaming. Every cellular provider has a database called the home location register, or HLR, where complete information regarding each subscriber is kept. They also maintain a database called the VLR, or visitor location register, that maintains information on each caller who visits from other areas. When a cellular subscriber roams, each network they visit exchanges SS7 messages with their “home” network. The subscriber’s home system also marks its HLR so that it knows where to send calls for its customers who are roaming.

SS7 has three major components:

1. Packet switches – Signal Transfer Points that route signals between databases and central switches. STPs, or Signal Transfer Points, are responsible for translating the SS7 messages and then routing these messages amongst the various network nodes and databases. Signal Transfer points are packet switches that route signals between central offices as specialized databases. Messages are sent between points on the SS7 network in variable-length packets with the addresses attached. Signal transfer switches read only the address portion of the packets and forward the messages accordingly.

2. Service Switching Points – Software and ports in central offices that enable switches to query databases. SSPs are the switches that begin and end calls. They receive signals from the Customer Provided Equipment (CPE) and then process the calls on the behalf of the end users. The user triggers the network to provide various services by dialing particular digits. SSPs are typically implemented at access tandem offices, local exchanges or toll centers that contain the needed network signaling protocols. The SSP serves as the begining and ending point for SS7 messaging.

3. Service Control Points – DBs with customer feature and billing information. Service Control Points, or SCPs, interface with SSPs as well as STPs. The STP contains the network configuration and call-completion database – the SCP contains all the service logic that is needed to deliver the type of call and feature in the call that the user is requesting. SCPs are centralized network nodes that contain software and databases needed for call management. Functions such as digit translation, call routing and verification of credit cards are all provided by SCPs. Usually a SCP will receive traffic from a SSP via the STP and will then return responses based on those queries by way of the STP.

The SS7 signaling data link is a full duplex digital transmission channel that operates at either 56 Kbs (T-Carrier transmission systems, in North America) or 64 Kbps (E_Carrier transmission systems, Europe). SS7 also defines a number of other types of links, each with a specific use within a SS7 network.

A (access) links
B (bridge) links, D (diagonal) links, and B/D links
C (cross) links
E (extended) links
F (fully associated) links

Geek T-Shirts, Decals, and more at http://www.tshirtnow.net

Want to know more?

You’re reading Boston’s Hub Tech Insider, a blog stuffed with years of articles about Boston technology startups and venture capital-backed companies, software development, Agile project management, managing software teams, designing web-based business applications, running successful software development projects, ecommerce and telecommunications.

About the author.

I’m Paul Seibert, Editor of Boston’s Hub Tech Insider, a Boston focused technology blog. I have been working in the software engineering and ecommerce industries for over fifteen years. My interests include computers, electronics, robotics and programmable microcontrollers, and I am an avid outdoorsman and guitar player. You can connect with me on LinkedIn, follow me on Twitter, follow me on Quora, even friend me on Facebook if you’re cool. I own and am trying to sell a dual-zoned, residential & commercial Office Building in Natick, MA. I have a background in entrepreneurship, ecommerce, telecommunications and software development, I’m a Technical PMO Director, I’m a serial entrepreneur and the co-founder of several ecommerce and web-based software startups, the latest of which are Twitterminers.com and Tshirtnow.net.

Add to FacebookAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to TwitterAdd to TechnoratiAdd to Yahoo BuzzAdd to Newsvine

Reynders and McVeigh, Boston Green Technology Fund, shares five green technology stock picks June 10, 2009

Posted by HubTechInsider in renewable energy.
Tags: , , , ,
add a comment

Reynders, McVeigh Capital Management is a Boston firm that picks green stocks for wealthy individuals. Recently, managing partner Charlton Reynders, who along with partner Patrick McVeigh formed the firm in 2005, talked about five of the company’s green technology picks for the future.

Reynders and McVeigh invest in a group of 25 to 35 companies that pass certain criteria on social, environmental, and economic factors. They claim that their $350 million portfolio lost 1.6% annually in the last three years, as compared to an 8.3% drop in the S&P 500.

They support a concept known as investing in the green revolution’s “backbone”. Backbone is defined as the suppliers of technologies other green ventures use to make riskier end-use products, such as solar panels, wind turbines and biofuels.

“Many green tech companies are one-shot wonders,” Reyders explains. As the credit crunch isn’t yet over, companies whose debt equals more than one-third of capital are potentially at risk.

One pick is Applied Materials. They entered the solar business three years ago and have such customers as China’s Suntech Power. The solar unit had sales of $819 million last year and lost $183 MM. They plan to expand into LED lighting over the next few years.

A second pick is Denmark’s Novozymes, which sells the enzymes used in corn-based ethanol production. They are working on the enzymes used in cellulosic-based ethanol and detergent enzymes that can displace polluting phosphates.

Danish company Vestas Wind Turbines is a third pick. They are a cheap stock and one with alot of potential upside.

Switzerland’s ABB is the world’s largest maker of equipment for electric power grids. These grids, worldwide, may need an upgrade in order to handle expanded green technology power generation and get that extra electricity to market efficiently.

For example, in China ABB is building a 1,250-mile high voltage DC power line to carry current up to 20% more efficiently from the Xiangjiaba Hydro Plant to Shanghai.

Another stock to watch grow in the new green technology economy is Deere & Co., which will benefit from the fitting of GPS sensors to more efficiently grade farmland and minimize water runoff and help to increase crop yields.

E Ink of Cambridge, MA to be acquired by their largest customer, Taiwan-based PVI (Prime View International) June 9, 2009

Posted by HubTechInsider in Hardware, Venture Capital.
Tags: , , , ,
add a comment

Cambridge-based E Ink Corporation will be acquired by Taiwan-based PVI (Prime View International), their largest customer, in a pending $215 million deal. E Ink employs about 120 people at their Cambridge, MA headquarters and another five or so employees at their just opened coating and film production plant in South Hadley, MA.

E Ink manufactures the key display technology used in devices such as the Amazon Kindle, Kindle DX and Kindle 2 and other brand electronic readers. This market is expected to grow rapidly; In a better stock market for Initial Public Offerings, or IPOs, a company such as E Ink would normally be able to turn to the public markets for expansion capital. But the IPO market in the US is very slow, with only seven IPOs so far on Wall Street this year.

The largest investor in the 12-year old company is FA Technology Ventures in Boston. One of their Managing Partners, Ken Mabbs, has a Board seat. Another financial backer of E Ink is Solstice Capital in Boston.

E Ink was founded in 1997 by CEO Russ Wilcox and four partners, one of whom was Joseph Jacobson from the MIT Media Lab. The company has raised more than $150 million in capital, from venture firms and also industry strategic partners such as Hearst Corp., Intel Corp., and Motorola.

Under the acquisition plan, E Ink would be a wholly owned subsidiary of PVI, retain its local management and employees, and help PVI refocus on the electronic paper market.

Within the past year, other Massachusetts-based startups have been purchased by foreign or out-of-state buyers, including companies such as Maven Networks, Virtual iron, Millennium Pharmaceuticals and Sirtis Pharmaceuticals – ranging in technologies from traditional networking technology to biotechnology.

What is an ACNA? What is a CCNA code in telecommunications? June 8, 2009

Posted by HubTechInsider in Definitions, Fiber Optics, Telecommunications, Uncategorized.
Tags: , , , ,
add a comment

An ACNA stands for Access Customer Name Abbreviation; It is a three-digit alpha code assigned to identify carriers, both ILECs (Incumbent Local Exchange Carriers) and CLECs (Competitive Local Exchange Carriers), for billing and other identification purposes.

It is closely related to the CCNA code, or the Customer Carrier Name Abbreviation, which identifies the common language code for the IXC (InterExchange Carrier) providing the interLATA facility.

The CCNA reflects the code to be contacted for provisioning whereas the ACNA reflects the IXC to be billed for the service.

Geek T-Shirts, Decals, and more at http://www.tshirtnow.net

Want to know more?

You’re reading Boston’s Hub Tech Insider, a blog stuffed with years of articles about Boston technology startups and venture capital-backed companies, software development, Agile project management, managing software teams, designing web-based business applications, running successful software development projects, ecommerce and telecommunications.

About the author.

I’m Paul Seibert, Editor of Boston’s Hub Tech Insider, a Boston focused technology blog. You can connect with me on LinkedIn, follow me on Twitter, even friend me on Facebook if you’re cool. I own and am trying to sell a dual-zoned, residential & commercial Office Building in Natick, MA. I have a background in entrepreneurship, ecommerce, telecommunications and software development, I’m the Senior Technical Project Manager at eSpendWise, I’m a serial entrepreneur and the co-founder of Tshirtnow.net.

Add to FacebookAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to TwitterAdd to TechnoratiAdd to Yahoo BuzzAdd to Newsvine

What is the Mu-Law PCM voice coding standard used in North American T-Carrier telecommunications transmission systems? June 8, 2009

Posted by HubTechInsider in Definitions, Telecommunications, VUI Voice User Interface.
Tags: , , , , , , , , ,
1 comment so far
Sampling and 4-bit quantization of an analog s...

Image via Wikipedia

Mu-Law encoding is the PCM voice coding standard used in Japan and North America. It is a companding standard, both compressing the input and expanding the data upon opening after transmission. Mu Law is a PCM (Pulse Code Modulation) encoding algorithm where the analog voice signal is sampled eight thousand times per second, with each sample being represented by eight bits, thus yielding a raw transmission rate of 64 Kps. Each sample consists of a sign bit, a three bit segment which specifies a logarithmic rqange, and a four bit step offset into the range. The bits of the sample are inverted before transmission. A Law encoding is the voice coding standard which is used in Europe.

Want to know more?

You’re reading Boston’s Hub Tech Insider, a blog stuffed with years of articles about Boston technology startups and venture capital-backed companies, software development, Agile project management, managing software teams, designing web-based business applications, running successful software development projects, ecommerce and telecommunications.

About the author.

I’m Paul Seibert, Editor of Boston’s Hub Tech Insider, a Boston focused technology blog. You can connect with me on LinkedIn, follow me on Twitter, even friend me on Facebook if you’re cool. I own and am trying to sell a dual-zoned, residential & commercial Office Building in Natick, MA. I have a background in entrepreneurship, ecommerce, telecommunications and software development, I’m the Senior Technical Project Manager at eSpendWise, I’m a serial entrepreneur and the co-founder of Tshirtnow.net.

Burlington, MA-based Exa sells Supercomputing as an on-demand service in the Cloud June 8, 2009

Posted by HubTechInsider in Supercomputing.
Tags: , , , ,
add a comment

Burlington, MA-based Exa sells supercomputing cycles as a Cloud service over the Internet.

Exa is a privately held 170-person outfit in burlington, MA that sells supercomputer time by the slice. The company was launched in 1992 by selling fluid dynamics simulation software one of its MIT founders created while a professor there.

The company owns a network of 3,500 Intel and AMD-based servers and has the capability to rent thousands more. These servers are housed by IBM in their Poughkeepsie, NY data center.

Exa charges around a dollar per processor core per hour for the supercomputer time, which is offered over the Internet using Exa’s modeling software as a “Cloud computing” option, much as Google lets users access documents and spreadsheets over the web or Amazon’s EC2 service rents out simple processing and storage capability.

Exa’s had revenues of $34 million in 2008, with on-demand supercomputer services accounting for $10.5 MM, up from 48% in 2007. Software sales grew a mere 13% to $21 million last year.

Selling supercomputing as a service is still just a tiny fraction of the $9.8 billion market for high-performance computing. But others such as oil-services firm Schlumberger are also selling supercomputing services to a select client base and industry vertical.

Exa has several customers with “bursty” supercomputing needs, such as Dodge and Peugeot, the U.S. National Bobsled Team, and tractor manufacturer Agco.

The Advantages and Disadvantages of Fiber Optics June 4, 2009

Posted by HubTechInsider in Fiber Optics, Telecommunications.
Tags: , , , , , , ,
10 comments
English: A TOSLINK fiber optic cable with a cl...

English: A TOSLINK fiber optic cable with a clear jacket that has a laser being shone onto one end of the cable. The laser is being shone into the left connector; the light coming out the right connector is from the same laser. (Photo credit: Wikipedia)

Advantages of fiber optics:

1. Extremely high bandwidth – No other cable-based data transmission medium offers the bandwidth that fiber does.

2. Easy to accomodate increasing bandwidth – Using many of the recent generations of fiber optic cabling, new equipment can be added to the inert fiber cable that can provide vastly expanded capacity over the originally laid fiber. DWDM, or Dense Wavelength Division Multiplexing, lends fiber optic cabling the ability to turn various wavelengths of light traveling down the fiber on and off at will. These two characteristics of fiber cable enable dynamic network bandwidth provisioning to provide for data traffic spikes and lulls.

3. Resistance to electromagnetic interference – Fiber has a very low rate of bit error (10 EXP-13), as a result of fiber being so resistant to electromagnetic interference. Fiber-optic transmission are virtually noise free.

4. Early detection of cable damage and secure transmissions – Fiber provides an extremely secure transmission medium, as there is no way to detect the data being transmitted by “listening in” to the electromagnetic energy “leaking” through the cable, as is possible with traditional, electron-based transmissions. By constantly monitoring an optical network and by carefully measuring the time it takes light to reflect down the fiber, splices in the cable can be easily detected.

Disadvantages of Fiber Optics:

1. Installation costs, while dropping, are still high – Despite the fact that fiber installation costs are dropping by as much as 60% a year, installing fiber optic cabling is still relatively costly. As installation costs decrease, fiber is expanding beyond its original realm and major application in the carrier backbone and is moving into the local loop, and through technologies such as FTTx (Fiber To The Home, Premises, etc,) and PONs (Passive Optical networks), enabling subscriber and end user broadband access.

2. Special test equipment is often required – The test equipment typically and traditionally used for conventional electron-based networking is of no use in a fiber optic network. Equipment such as an OTDR (Optical Time Domain Reflectometer)

is required, and expensive, specialized optical test equipment such as optical probes are needed at most fiber endpoints and connection nexuses in order to properly provide testing of optical fiber.

3. Susceptibility to physical damage – Fiber is a small and compact cable, and it is highly susceptible to becoming cut or damaged during installation or construction activities. Because railroads often provide rights-of-way for fiber optic installation, railroad car derailments pose a significant cable damage threat, and these events can disrupt service to large groups of people, as fiber optic cables can provide tremendous data transmission capabilities. Because of this, when fiber optic cabling is chosen as the transmission medium, it is necessary to address restoration, backup and survivability.

4. Wildlife damage to fiber optic cables – Many birds, for example, find the Kevlar reinforcing material of fiber cable jackets particularly appealing as nesting material, so they peck at the fiber cable jackets to utilize bits of that material. Beavers and other rodents use exposed fiber cable to sharpen their teeth and insects such as ants desire the plastic shielding in their diet, so they can often be found nibbling at the fiber optic cabling. Sharks have also been known to damage fiber optic cabling by chomping on it when laid underwater, especially at the repeating points. There is a plant called the Christmas tree plant that treats fiber optic cable as a tree root and wraps itself around the cable so tightly that the light impulses traveling down the fiber are choked off.

HubTechInsider.com YouTube Channel

Subscribe to HubTechInsider.com YouTube Channel

SEO Made Easy 2013 FREE Special Report!

PHP for Beginners

Google + Domination for Business

LinkedIn for Business Training Course

Mastering WordPress Video Training Course

Twitter Business Magic Video Tutorial Series

Want to know more?

You’re reading Boston’s Hub Tech Insider, a blog stuffed with years of articles about Boston technology startups and venture capital-backed companies, software development, Agile project management, managing software teams, designing web-based business applications, running successful software development projects, ecommerce and telecommunications.

About the author.

I’m Paul Seibert, Editor of Boston’s Hub Tech Insider, a Boston focused technology blog. You can connect with me on LinkedIn, follow me on Twitter, even friend me on Facebook if you’re cool. I own and am trying to sell a dual-zoned, residential & commercial Office Building in Natick, MA. I have a background in entrepreneurship, ecommerce, telecommunications and software development, I’m the Senior Technical Project Manager at Cartera Commerce, I’m a serial entrepreneur and the co-founder of Tshirtnow.net.

Eight ways to tell if your Project Team is on the Way Up, or on the Way Down

What is ‘Management By Walking Around’?

What is Scrum?

What is a “Use Case”?

What is a “User Story”?

The Twenty Laws of Testing Computer Software

Add to Google Buzz

Like This!

Add to FacebookAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to TwitterAdd to TechnoratiAdd to Yahoo BuzzAdd to Newsvine

How to expand your professional network on LinkedIn June 3, 2009

Posted by HubTechInsider in Social Media.
Tags: ,
1 comment so far

Metcalfe’s Law: The value of a network increases in proportion to the square of connections.

(The following text is from a note I wrote in response to a sincere letter from one of my professional contacts on LinkedIn who asked me how I am able to expand my network of professional contacts on LinkedIn to such a great degree in such a short amount of time. There are ongoing debates about quantity vs. quality that rage online. I am of the school that you need a high quantity of high quality connections in order to experience the benefits of “Network externalities” or “Network effects”, in much the same manner as I have written about regarding Twitter. A large network allows you to see deep within organizations, check out potential employers, potential hires, and find out so much more than just having a few professional connections affords you. The point of networking isn’t to have communications amongst people already in your address book or the people you currently work with; The point of networking is to expand your professional horizons and connect with people you don’t know but would like to.)

Hi Jim –

Please feel free to contact me at any time with any requests or questions – I love to help any of my professional contacts!

There are a couple of simple techniques you can use to increase your connections on LinkedIn in order to expand your professional network:

1. Research and read articles and blog posts from the LinkedIn experts: I highly recommend Guy Kawasaki’s articles on LinkedIn, and there are many others that are just a Google search away. I read many of these articles and it helped me tremendously.

2. Join Groups on LinkedIn and post connection requests there (if they are allowed) – in LinkedIn groups where they are not officially allowed, you can usually get away with starting a discussion and then placing your connection request at the end or in your signature. This is a very effective technique.

3. If you have a personal blog, place a link to your LinkedIn profile there, as I have done:

https://hubtechinsider.wordpress.com/my-technology-experience/

and then you can get lots of connection requests from that avenue. People like to connect to people in their field of interest or vocation.

4. Start incorporating LinkedIn connection requests into your other online communications (email, facebook, twitter, etc.) to gain more connections.

5. Work on getting your present and past friends and work associates to link with you on LinkedIn.

6. I highly recommend joining an organization known as TopLinked.com, now known as OpenNetworker.com – for $10 / mth., you will begin receiving many requests for connections. I recommend you do research on LinkedIn using the sources I described above in order to decide if a vastly expanded network of professional contacts on LinkedIn is for you. I find that it helps greatly in providing an enhanced “vision” into companies and organizations that you just cannot get with a small number of connections. One of the points of networking is to expand your professional horizons, and that doesn’t really mean connecting to people you already know. Opennetworker.com is also a way of networking, not just some paid service. It means leaving your connections open for viewing on LinkedIn, providing introductions for people from your network of professional contacts, and providing help to people who sincerely request it as you have done. Provide help, information, and networking to your connections. Be a good networker by putting in the effort. It also means never hitting the “I don’t know this user” button; If someone requests a connection you’d rather not be connected with, simply archive the request. Someone reached out to you — don’t repay their efforts with a rude act like hitting “IDK”, as it has repercussions on LinkedIn for people who are simply trying to expand their professional horizons.

Having a large professional network can bring you benefits down the road that you are not even aware of at present. It has already brought me alot of joy. Think of what is called “Network externalities”, or “Network effects”. These concepts are behind the very underpinnings of the World Wide Web and the Internet. Start using them to your advantage.

I hope this helps; Thanks for your nice note Jim!

– Paul

(By the way, if you are currently on LinkedIn and would like to connect with me, please don’t hesitate to send me an invitation to connect on LinkedIn – thanks for reading my blog!)

Add to FacebookAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to TwitterAdd to TechnoratiAdd to Yahoo BuzzAdd to Newsvine

Want to know more?

You’re reading Boston’s Hub Tech Insider, a blog stuffed with years of articles about Boston technology startups and venture capital-backed companies, software development, Agile project management, managing software teams, designing web-based business applications, running successful software development projects, ecommerce and telecommunications. You can subscribe to Hub Tech Insider’s RSS feed.

About the author.

I’m Paul Seibert, Editor of Boston’s Hub Tech Insider, a Boston focused technology blog. You can subscribe to Hub Tech Insider’s RSS feed in your RSS feed reader. You can connect with me on LinkedIn, follow me on Twitter, even friend me on Facebook if you’re cool. I own and am trying to sell a dual-zoned, residential & commercial Office Building in Natick, MA. I have a background in entrepreneurship, ecommerce, telecommunications and software development, I’m the Senior Technical Project Manager at eSpendWise, I’m a serial entrepreneur and the co-founder of Tshirtnow.net.

What is the frequency response of the North American Public Switched Telephone Network? June 3, 2009

Posted by HubTechInsider in Telecommunications, VoIP, VUI Voice User Interface, Wireless Applications.
Tags: , , , , , , ,
1 comment so far
Sinusoidal waves of various frequencies; the b...

Image via Wikipedia

The conventional North American Public Switched Telephone Network, or PSTN, has a frequency response range of 300 Hz to 3,400 Hz. The normal hearing range of humans is typically 30 Hz to 20,000 Hz. So the conventional telephone transmission system is unable to carry bright, high-frequency and deep, low-frequency tones.

But, somewhat surprisingly, because our ears are so used to hearing poor-quality audio over the telephone, our brains actually “fill in” the missing frequencies. As an example, the crisp “s” sound in the word “Christmas”. So in effect, the telephone audio often sounds better than it actually is to us.

An explanation of the Nyquist Theorem and its importance to Mu-Law Encoding in North American T-Carrier Telecommunications Systems June 2, 2009

Posted by HubTechInsider in Definitions, Fiber Optics, Mobile Software Applications, Telecommunications, VUI Voice User Interface, Wireless Applications.
Tags: , , ,
add a comment

nyquist100

The Nyquist theorem established the principle of sampling continuous signals to convert them to digital signals. In communications theory, the Nyquist theorem is a formula stating that two samples per cycle is all that is needed to properly represent an analog signal digitally. The theorem simply states that the sampling rate must be double the highest frequency of the signal. So, for example, a 4KHz analog voice channel must be sampled 8000 times per second. The Nyquist Theorem is the mathematical underpinning of the Mu-Law encoding technique used in T-Carrier transmission systems. T-Carrier is used in North American telecommunications networks. In Europe, where E-carrier transmission systems are used, a similar but incompatible theorem, Shannon’s Law, is used in the European A-Law encoding technique. This is the reason why Mu-Law encoding is used in North America and A-Law encoding is used in Europe.

The author of the Nyquist Theorem was named Harry Nyquist. Harry worked in the research department at AT&T and later at Bell Telephone Laboratories. In 1924, he published a paper titled “Certain Factors Affecting Telegraph Speed”, which analyzed the correlation between the speed of the telegraph system and the number of signal values it used. Harry refined his paper in 1928, when he republished his work under the title “Certain Topics in Telegraph Transmission Theory”. It was in this paper that Harry expressed the Nyquist Theorem, which established the principle of using sampling to convert a continuous analog signal into a digital signal. Claude Shannon, the author of Shannon’s Law, cited both of Nyquist’s papers in the first paragraph of his classic paper “The Mathematical Theory of Communication”. Harry Nyquist is also known for his explanation of thermal noise, also sometimes known as “Nyquist noise” as well as AT&T’s 1924 version of a fax machine, called “telephotography”.

His remarkable career included advances in the improvement of long-distance telephone circuits, picture transmission systems, and television. Dr. Nyquist’s professional, technical, and scientific accomplishments are recognized worldwide. It has been claimed that Dr. Nyquist and Dr. Claude Shannon are responsible for virtually all the theoretical advances in modern telecommunications. He was credited with nearly 150 patents during his 37-year career. His accomplishments underscore the excellent preparation in engineering that he received at the University of North Dakota. In addition to Nyquist’s theoretical work, he was a prolific inventor and is credited with 138 patents relating to telecommunications.





Want to know more?

You’re reading Boston’s Hub Tech Insider, a blog stuffed with years of articles about Boston technology startups and venture capital-backed companies, software development, Agile project management, managing software teams, designing web-based business applications, running successful software development projects, ecommerce and telecommunications.


About the author.

I’m Paul Seibert, Editor of Boston’s Hub Tech Insider, a Boston focused technology blog. You can connect with me on LinkedIn, follow me on Twitter, even friend me on Facebook if you’re cool. I own and am trying to sell a dual-zoned, residential & commercial Office Building in Natick, MA. I have a background in entrepreneurship, ecommerce, telecommunications and software development, I’m the Senior Technical Project Manager at eSpendWise, I’m a serial entrepreneur and the co-founder of Tshirtnow.net.

Add to FacebookAdd to DiggAdd to Del.icio.usAdd to StumbleuponAdd to RedditAdd to BlinklistAdd to TwitterAdd to TechnoratiAdd to Yahoo BuzzAdd to Newsvine

%d bloggers like this: