Advanced BGP - Conditional Matching
6 important questions on Advanced BGP - Conditional Matching
What two categories of Access Control Lists (ACLs) are there?
Extended ACL: Define packets on Source, Destination, Protocol, Port or other packet attributes.
Both Standard and Extended ACLs can be Named or Numbered. What numbers can be given to the ACLs?
100-199 and 2000-2699 for extended ACLs
When using ACLs for IGP Network Selection, which type of ACL is used and how?
So permit ip host 172.16.0.0 host 255.255.0.0 means the network 172.16.0.0/16 is selected.
- Higher grades + faster learning
- Never study anything twice
- 100% sure, 100% understanding
How do Extended ACLs work when used for matching BGP Routes?
permit ip 172.16.0.0 0.0.255.255
255.255.255.128 0.0.0.127
This means look in the network 172.16.0.0/16 for network matches that have a subnet mask of /25 to /32.
Instead of ACLs to identify networks in a routing protocol, a simpler option would be to use Prefix Matching. How does Prefix Matching work?
10.0.0.0/8 ge 22 le 26
Means any subnet in the 10.0.0.0/8 range with a mask equal or greater then 22 and equal or lesser than 26
How are Regular Expressions used in BGP when identifying routes?
This matching is done user Regular Expressions against the AS Number.
The question on the page originate from the summary of the following study material:
- A unique study and practice tool
- Never study anything twice again
- Get the grades you hope for
- 100% sure, 100% understanding