Contrary to what you may have been told, IP does not necessarily mean “In for Problems.” IP is the acronym for Internet Protocol which is the set of techniques used by many hosts for transmitting data over the Internet. The current version of the Internet protocol is IPv4, which provides a 32-bit address system.
Internet protocol is a "best effort" system, meaning that no packet of information sent over it is assured to reach its destination in the same condition it was sent. Often other protocols are used in tandem with the Internet protocol for data that for one reason or another must have extremely high fidelity.
Every device connected to a network, be it a local area network (LAN) or the Internet, is given an Internet protocol number. This address is used to identify the device uniquely among all other devices connected to the extended network.
TCP/IP (Transmission Control Protocol/Internet Protocol) is the basic communication language or protocol of the Internet.
TCP/IP is a two-layer program. The higher layer, Transmission Control Protocol, manages the assembling of a message or file into smaller packets that are transmitted over the Internet and received by a TCP layer that reassembles the packets into the original message. The lower layer, Internet Protocol, handles the address part of each packet so that it gets to the right destination.
TCP/IP uses the client/server model of communication in which a computer user (client) requests and is provided a service (such as sending a Web page) by another computer (server) in the network. TCP/IP communication is primarily point-to-point, meaning each communication is from one point (or host computer) in the network to another point or host computer. TCP/IP and the higher-level applications that use it are collectively said to be "stateless" because each client request is considered a new request unrelated to any previous one (unlike ordinary phone conversations that require a dedicated connection for the call duration). Being stateless frees network paths so that everyone can use them continuously.
Most but not all TCP/IP uses Ethernet-based networks. Ethernet networks use the familiar RJ-45 connectors and Category cable.
There are four unshielded twisted pairs in a Category 5 cable. Currently Category 5e is the flavor of the day in networking, with Category 6 standing in the wings waiting to take center stage.
Security applications have different bandwidth requirements. Video requires high bandwidth, while access control typically will require far less.
Category 6 is rated for Gigabit network speeds. CAT 5 cable will support 10/100 Ethernet; also referred to as Ethernet and Fast Ethernet.
CAT 5e cable will support Ethernet, Fast Ethernet, and Gigabit Ethernet. It is completely backwards compatible, and can be used in any application in which you would normally use CAT 5 cable.
Cross talk is the electrical interference that results when one wire's signal effects another wire's signal.
CAT 5e cable provides a significant performance enhancement over Category 5 with respect to crosstalk.
Bandwidth is the information-carrying capacity of a system. The greater the bandwidth, the greater the information-carrying capacity in a given period of time.
CAT 5e cable is rated at 350 megahertz. This increased bandwidth (compared to CAT 5 cable) that allows it to support Gigabit Ethernet.
The slowest element in a network will throttle down the maximum bandwidth of the network, but the network must be designed to accommodate the fastest device connected to it, or performance will suffer, and your client will not be happy.
We all have experienced sluggish network performance which results in choppy video, or interruptions of downloads or opening of web pages.
In security applications, sluggish network performance can result in a disaster rather than just an annoyance.
IP technology has achieved a relatively high performance level and has found acceptance and has entrenched itself in security technology, so it is a necessity that security professionals have at least a working knowledge of it,