OSPF over Frame-relay

I just wanted to drop a line that has helped me tremendously the last couple of months. Its hard to remember sometimes what goes into an ospf config when using frame as your medium. Remember this:

"Non-broadcast Needs Neighbors"

If the network type is the default of non-broadcast, or point-to-multipoint non-broadcast you will have to include neighbor statements in your ospf configs. HTH's!

-Jason

Routing Protocols Comparison Poster

I kind of threw this together for my written. It is a pdf in its natural state, if you want a copy of the pdf email me at willroute4food at gmail dot com. Its just a good quick side-by-side of some of the major routing protocols. If you find an error, or something I should add please let me know in the comments (I do realize some of the numbers were thrown off in the conversion. The data does appear to be in the appropriate containers though). Thanks.

	RIP (version 2)	OSPF	EIGRP	BGP
IP Protocol number, (TCP)	n/a	IP 89	IP 88	TCP 179
Hello Address	224.0.0.9 (can be set to broadcast at the interface level via ip rip v2-broadcast)	224.0.0.5 –AllOSPFRtrs 224.0.0.6 –DR/BDR	224.0.0.10	Unicast hello to configured “neighbor”
Administrative Distance(s)	120	110	Internal – 90 External – 170 Summary -- 5	EBGP – 20 IBGP – 200
Metric (calculation) / Limits	Hop Count/ Limit is 15 hops, 16 is inaccessible	Cost = Autocostrefbw/interface bandwidth *Default is 100Mb for Autocostrefbw*	Cost  = 256(BW + Delay) *formula with default K values) The maximum number of hops that EIGRP will accept is 100 by default, although the maximum can be configured to 220 with metric maximum hops.	IBGP – 0 Redistributed routes metric = IGP metric
Timers	Update-30 Invalid-180 Holdown-180 Flush-240	Hello – 10/30 Dead – 40/120	Hello – 5/60 Hold – 15/180	Keepalive – 60 Holdtime -- 180
Adjacency (neighbor) Requirements	Neighbor must be on a subnet off of primary interface included in “network” statement	1.       Pass authentication checks 2.       Same primary subnet w/mask 3.       Same OSPF area 4.       Same Area type (flags) 5.       NOT duplicate RIDS 6.       Hello/Dead timers must match 7.       Unless P2P (one must be DR/BDR)	1.       Pass authentication checks 2.       Must have same AS number 3.       Must believe that source IP of neighbor in hello is in that routers primary subnet (no secondary’s) 4.       K values must match	1.       Source IP in connection request must match something in the local routers “neighbor” statements. 2.       Routers ASN must match its corresponding ASN in “neighbor stmt 3.       RIDS must be different 4.       Must pass MD5 authentication
Passive Interface (yes,no) /Affects	Yes/Shuts off the sending of updates on the passive interface.  Will still listen to updates and will update routing table accordingly	Yes/Stops sending hello’s /updates out of that interface.  Note though, if included in the network statement the network on that interface will still be advertised to peers.	Yes/suppresses both incoming AND outgoing hellos/updates.  Note that it will not allow neighbors to form.	n/a
Auto-summarization	Enabled by default	n/a	Enabled by default (wont summarize route that it does not “own”)	Disabled by default after 12.3 mainline
Summary Address	(conf-if) ip summary-address rip ip-address ip-network-mask default-information originate [route-map map-name]	ABR- area x range ip-address mask {advertise | no-advertise} cost cost (router) summary-address ip-address mask	(conf-if) ip summary-address eigrp [as] ip-address mask	aggregate-address address mask [as-set] [summary-only] [suppress-map map-name] [advertise-map map-name] [attribute-map map-name] neighbor x.x.x.x default-originate network 0.0.0.0 (OR STATIC ROUTE/REDISTRIBUTE)
Filtering Method(s)	distribute-list {access-list-number | prefix prefix-list-name [gateway prefix-list-name]} in [interface-type interface-number]	Inbound – distribute-list {prefix | route-map} in In/out – area (number) filter-list prefix (name) {in | out}	Distribute-list {access-list num/name}  {prefix list-name}  {in | out}  {int type/num}	Prefix-lists, route-maps, filter-lists, etc….
Authentication	Clear text or MD5 16 character limit Key chain RIP Key 1 Key-string cisco Int fa0/0 Ip rip authentication key-chain RIP Ip rip authentication mode md5	0 – none, 1 – clear text, 2 – MD5 Int fa0/0 Ip ospf authentication Ip ospf authentication-key {key} Int fa0/0 Ip ospf authentication message-digest Ip ospf message-digest-key {number} md5 {key} You can also declare the authentication type under the router OSPF process	MD5 only Key chain EIGRP Key 1 Key-string cisco Int fa0/0 Ip authentication mode eigrp [as] md5 Ip authentication key-chain EIGRP [as] EIGRP	MD5 only Neighbor x.x.x.x password [pass]
Offsets	Increases incoming or outgoing hop count on routing updates (CAN BE USED TO FILTER BY SETTING HOP COUNT > 15) Access-list 1 permit 10.10.10.0 0.0.0.255 Router rip Offset-list 1 out 5 serial0 //increases metric by 5 on that route//	n/a	access-list 1 permit 10.1.1.0 0.0.0.255 router eigrp 1 offset-list 1 out 3 FastEthernet0/0	n/a