Usesful Acronyms for CCNA/CCNP

1. 3DES Triple DES
2. 6-to-4 IPv6-to-IPv4
3. AAA Authentication, authorization, accounting
4. ABR Area Border Router
5. ACK acknowledge, acknowledgment, acknowledgment bit in a TCP segment
6. ACL access control list
7. ACS Access Control Server
8. AD advertised distance
9. ADSL asymmetric DSL

PACKET FILTERING ?

 PACKET FILTERING ?

1. A malicious user can still discover what is packets meet the pix firewall criteria and send arbitary traffic.
2. Packet can get through by being fragmented.
3. complex access control lists are difficult to configure and cumbersome to maintain.
4. Not all services can be packet filtered.

Firewall

what is firewall ?

firewall is a system of hardware and or software that controls access between 2 or more networks.

Basics of Networking

WHAT IS VLAN