Linux Networking Cookbook

Appendix B. Glossary of Networking Terms

A

Active Directory

Microsoft’s implementation of LDAP used in Windows environments. Active Directory is a directory service primarily used to provide authentication services for Windows computers, but can also be used to store any information about a network or organization in a central database designed to be quickly accessible. The data in Active Directory’s database is held in one or more equal peer Domain Controllers, each of which holds a copy of all information within the Active Directory, and synchronizes changes made on one DC to all others. Compare this to pre-Windows 2000 Server systems, which used a Primary Domain Controller and multiple Backup Domain Controllers.

AGP—Accelerated Graphics Port

Originally, graphics cards didn’t need any more bandwidth than a PCI slot could provide, but the more they developed, the more bandwidth they took from the PCI bus—eventually requiring a dedicated connection. The AGP slot was created specifically to cater to the bandwidth requirements of high performance graphics cards. Based on the architecture of a PCI slot, an AGP port is a dedicated single port, not just one slot of many on a shared bus. This means the AGP card gets all the bandwidth on that connection to itself, without having to share with anything else. Since the rise in popularity of PCIe slots (which can provide much higher bandwidth), fewer new motherboards are being released with AGP ports.

ATM—Asynchronous Transfer Mode

High-speed networking ...