Security, Stability, and Interoperability Issues on VoIP ImplementationWritten by Al Falaq Arsendatama
Now we have accepted that VoIP is no longer just a phone service, it has become feature rich as it merges with computer configurations. The VoIP's existence has changed considerably over last few years, coupled with availability of broadband connection to Internet, plus leaps in multimedia technology in which virtual operations with remote sites becomes more enhanced, makes VoIP service a viable alternative to traditional communication offerings.
Cost savings is not only driving force for VoIP implementations, enterprises have to consider some business aspects that VoIP can bring about. VoIP creates potentials for applications that could not have been done before. Collaboration, integration, and interactivity between employees and applications are one of several business benefits that enterprises can derive from VoIP adoption. Nevertheless, amid euphoria of VoIP technology, there are three important aspects to look at before a company goes VoIP. In following paragraphs I will summarize aspect of security, stability, and interoperability that play a key role in successful implementation of VoIP.
VoIP implementations may expose new security risks and challenges that somehow become greater concern than quality and cost-efficiency among vendors and users. VoIP networks are vulnerable to all same security risks as traditional IP data networks, including:
- Denial of Service (DoS), viruses, worms,
- Toll fraud and unauthorized access,
- Spoofing, and port scanning.
It is recommended that organizations should adopt a layered, defense-in-depth security strategy to address issue with increasing proliferation of new Internet-borne attacks and malicious activities in recent years. In this architecture, network is segmented into secure zones protected by layers of firewall, intrusion prevention, and other security services. This strategy allows organizations to logically split and secure voice and data networks in front of individual voice and data components and between interactive points in network.
One of main issues of VoIP is amount of bandwidth required for each call. There must be adequate bandwidth reserved and quality of link must be well maintained throughout each call to ensure users are not affected. As very nature of VoIP call is real-time, any disruption during call would be easily noticeable and unacceptable. The two issues that enterprises usually have to deal with here are bandwidth and quality of service (QoS).
VoIP calls need a data transmission speed of 64kb/s to produce quality of voice comparable to that of a normal telephone call. That 64kb/s channel needs to remain open and unaffected for duration of call. Theoretically, VoIP installations would not allow such a huge bandwidth to be allocated for VoIP alone. Therefore, there needs to be a compression taking place to compact voice data into a considerable size before it gets transmitted over a packet switching network. G.723 codec that is incorporated in VoIP standard protocol H.232 can take a 64kb/s stream of data and squash it down to a mere 5.5kb/s or so. Generally, for VoIP to work reliably over WAN links, there has to be low jitter, low packet loss, a considerably high-speed connection between endpoints, and less than 200ms delay.
Microsoft Great Plains: Offshore Customization & Development – overview for consultantWritten by Andrew Karasev
When you visit department stores and see that majority of apparels are produced in other countries, not US – you probably do not worry about this fact. About 10 years ago, when Clinton’s high tech era was at inception – we saw signs of high tech professionals inflow in USA from overseas. Nowadays trend is reversed – instead of importing high tech people, we are at beginning of outsourcing to them in their overseas countries programming workload. In this small article we’ll concentrate on Microsoft Business Solutions Great Plains customization specifics: Great Plains Dexterity (IDE and programming language), SQL programming with XML in/out bound, VBA/Modifier/Continuum, Crystal Reports, Web publishing/eCommerce •Closed/Protected technology. Great Plains Dexterity serious development requires months of formal training and it also requires access to so-called source code (DYNAMICS.DIC with scripts in it – normally scripts are stripped). This fact imposes restrictions on offshore facility selection. This facility should be located in country, where Great Plains Software had former development force. To give you more clue – these are Australia and Philippines. If you are considering India – we do not know if anyone there has access to source code, at least officially they do not have access, because source code partner program was closed many years ago. •Coded table names: RM00101, SOP30200 – to give you example. The reason was – Dexterity design was based on multi-database-platform principle. From development standpoint – it means that developer should have data fixing experience – serving real clients either remotely to US or in their local countries