My Netwok Dictionary

Authentication

Here’s how to configure authentication keys for each router participating in the EIGRP routing process:

R1 # conf t
R1(config)# key chain EIGRP-KEYS
R1(config-keychain)# key 1
R1 (config-keychain-key) # key-string cisco

A2 # conf t
R2 (config) # key chain EIGRP-KEYS
R2 (config-keychain) key # 1
R2 (config-keychain-key) # key-string cisco

Key verification

R1 # show key chain
Key-chain EIGRP-KEYS:
key 1 - text “cisco”
accept lifetime (always valid) - (always valid) [valid now]
send lifetime (always valid) - (always valid) [valid now]

Now that our keys are configured in the router, you must apply to each interface on which you want to authenticate.

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There are five types of EIGRP packets:

- Hello: used for the dynamic creation of adjacencies. They are sent to multicast address 224.0.0.10 and do not require ACK. The time interval between sending a hello packet and the immediately following is called the hello interval. For connections with high bandwidth that time is 5 seconds (default), but for slower links (with bandwidth <= T1) amounts to 60 seconds. Furthermore, adiancenza is removed at the end of the so-called hold time (default is 3 times the hello interval), the number of seconds to wait without receiving a hello before the router declares the neighbor unreachable. Read the rest of this entry »

To check the routing tables, running the command show ip route:

Router # show ip route
Codes: C - connected, S - static, I - IGRP, R - RIP, M - mobile, B - BGP
D - EIGRP, EX - EIGRP external, O - OSPF, IA - OSPF inter area
N1 - OSPF NSSA external type 1, N2 - OSPF NSSA external type 2
E1 - OSPF external type 1, E2 - OSPF external type 2, E - EGP
i - IS-IS, L1 - IS-IS level-1, L2 - IS-IS level-2, * - candidate default
U - per-user static route, o - ODR
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Router (config) # router IGRP 100
Router (config-router) # network 192.168.1.0
Router (config-router) # network 200.200.1.0
Router (config-router) # variance?
<1-128> Metric variance multiplier
Router (config-router) # variance 2
Router (config-router) # traffic-share?
Share inversely proportional to balanced metric
Among min All traffic shared min metric paths Read the rest of this entry »

Router (config-router) # auto-summary
Restores the default behavior of automatic summarization of subnet routes into network-level routes.

Router (config-router) # default-information originate [route-map mapname]
Generates a default route. “Route” map mapname “is optional and will generate the default route if the route map is satisfied.

Router (config-router) # default-metric [number]
Sets the metric values for RIP perdeterminados, “number” = metric by default.

Router (config-router) # ip rip authentication key-chain [name-of-chain]
Package Enables authentication for RIP Version 2 (RIPv2 or RIP2). “Name-of-chain” specifies the set of keys or tools to use on an interface. Read the rest of this entry »

Today there are three different versions: RIPv1, RIPv2, and RIPng.

RIPv1: Version 1 RIP routing protocol is “classy”, i.e., does not support subnetting, VLSM or CIDR, has no authentication mechanisms and does not perform updates triggered by events. All these limitations led to the passage of time and changing needs fall into disuse.

RIPv2: Version 2 of RIP routing protocol is “classless”, supports subnetting, VLSM, CIDR, short routes, has mechanisms plain text authentication or MD5 encryption, performs updates triggered by events.

RIPng: version ng of RIP routing protocol is RIP for IPv6 deployments. If you are interested can read the specifications here. Read the rest of this entry »

The routing protocol EIGRP (Extended Internal Gateway Routing Protocol), and Cisco proprietary enhanced version of IGRP is a hybrid protocol that has characteristics of both distance vector and link state and is usually used in medium to large networks.

EIGRP Features

1. Default Metrics: Bandwidth + Delay.
2. It has an administrative distance of 90 domestic and 170 foreign.
3. Supports up to 255 dives (100 by default).
4. Using the DUAL algorithm for upgrades and fast convergence.
5. Partial updates triggered by events.
6. Supports IP, IPv6, IPX and AppleTalk.
7. Supports classless routing, VLSM arbitrary and summary routes.

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OSPF (Open Shortest Path First or First Shortest Route Free) is a routing protocol IGP (Interior Gateway Protocol) link-state used in large networks.

OSPF features:

1. Metric: Cost (Bandwidth Cisco IOS).
2. Administrative distance: 110.
3. Fast convergence and scalability.
4. Supports classless routing, VLSM and route summary.

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