Addressing the Issues
Properly addressing these issues requires active participation from IT in the security project. Involve IT at the initial concept stage. Brief them on all relevant aspects of the project, including the purpose and objectives, initial timetable and general approach. Don't make the mistake of thinking that it's just IT security personnel that must be involved.
There are usually significant network design and evaluation tasks involved, in addition to network security. Have security provide IT with a single-line diagram of the computers and network connections of the proposed security system, including all wireless devices. The drawing should show what kind of data will be sent between what computers (such as e-mail, video streams, reports of alarm history, data entry to enroll users), and any external systems interfaced, such as paging systems or radios.
Identify the protocols that will be used for each type of security data to be carried on the network. When in doubt as to whether to include information, include it. If computers on the business network require access to the security system, include the business computers in the diagram as well. Identify those elements that are "must-have" and those that are desirable but not absolutely necessary.
Include the estimated bandwidth requirements for each network connection. You may have to consult with current or prospective vendors to get the information you need to determine the bandwidth requirements using scenario-based requirements assessment, for which I've included guidelines later in this article. Share the method used to estimate the security network bandwidth with IT.
Have IT determine how many of the internetworking requirements can be supported by existing network infrastructure, and what new infrastructure (if any) would be needed, along with ballpark estimates on the costs involved. Have IT present this information to security, and answer any questions that result.
Have IT provide a list of computer operating system, software and hardware standards, network standards, and network security standards (such as for remote access) with which any security system vendor must comply. Have the vendor review the requirements and incorporate them into any proposed system project.
Have IT provide a drawing of the network infrastructure that it will furnish for the security network and for the business network connections. The drawing should identify the type of each network segment (microwave, Telco line, etc.) and the maximum bandwidth capability of each segment.
Have the security system vendor verify the compatibility of security system network traffic with the proposed network infrastructure. This will require discussions with IT department personnel and perhaps also with vendors that provide the network technology to IT.
If any incompatibilities are discovered, get together with IT, the security system vendor and the network technology vendors to explore the possible resolutions. Review the security project budget estimates and incorporate any new information provided by the IT and security vendors.
Review the security project schedule to make sure it takes into account the time frames for installing any network infrastructure that doesn't yet exist.
A significant amount of work is involved in most of these steps, especially for those who have not been through them before. While these are not necessarily all the information sharing steps that need to be taken, they are the major ones, and the remainder should fall out from these.
Security Network Bandwidth
Bandwidth is one of the most troublesome issues in internetworking projects. Bandwidth generally refers to the amount of information that can be carried in a given time period (usually a second) over a wired or wireless communications link. Any digital or analog signal has a bandwidth.