Glossary
gateway
gateway | An entrance and exit into a communications network |
Graphical User Interface | GUI, pronounced “GOOEY”. A set of screen presentations and metaphors that utilize |
(GUI) | graphic elements such as icons in an attempt to make an operating system easier to use. |
ground | A physical connection to the earth or other reference point. |
ground start (GS) | A method of signaling on subscriber trunks in which one side of the two wire trunk |
| (typically the ring conductor of Tip and Ring) is momentarily grounded to get dial tone. |
hash algorithm | A one way function that takes an input message of arbitrary length and produces a fixed |
| length digest. Adit uses both Secure Hash Algorithm (SHA) and Message Digest 5 (MD5) |
| hashes within our implementation of the IPSec framework. |
High Density Bipolar 3 | HDB3. A bipolar coding method that does not allow more than 3 consecutive zeros. |
hop | Each individual short trip that packets make from router to router, as they are routed to their |
| destination. |
host | A computer that allows users to communicate with other host computers on a network. |
impedance | The total opposition a circuit offers to the flow of alternating current. It is measured in ohms |
| and the lower the ohmic value, the better the quality of the conductor |
internet | “A network of networks,” the Internet supports FTP, WWW, Gopher, |
| |
| ISPs provide an effective interface with the Internet. The Internet itself is made up of |
| thousands of LANs and WANs, all using TCP/IP to provide information services to |
| millions of users. A worldwide network of networks that all use the TCP/IP |
| communications protocol and share a common address space. |
Internet Protocol (IP) | Internet Protocol, the method by which most Internet activity takes place. Members with |
| access to TCP/IP through a SLIP or PPP connection can connect to many ISP services in |
| this manner. As the name implies, it is a protocol for network activity. Most current |
| networks support some sort of TCP or IP directly or indirectly. |
IP address | A string of four numbers separated by periods (such as 111.22.3.144) used to represent a |
| computer on the Internet. The format of the address is specified by the Internet Protocol in |
| RFC 791. Each of the four number must be 255 or less; they may be 0. |
IPSec | IPSec (IP Security) is a set of IP extensions developed by IETF to provide security services |
| compatible with the existing IP standard (IPv.4) and also the upcoming one (IPv.6). In |
| addition, IPSec can protect any protocol that runs on top of IP, for instance TCP, UDP, and |
| ICMP. The IPSec provides cryptographic security services. These services allow for |
| authentication, integrity, access control, and confidentiality. IPSec allows for the |
| information exchanged between remote sites to be encrypted and verified. You can create |
| encrypted tunnels (VPNs), or just do encryption between computers. |
jitter | Interference on an analog line caused by a variation of a signal from its reference timing |
| slots. Jitter can cause problems in the receipt of data and any subsequent processing of that |
| data. |
Adit 3104 - Release 1.6 |
