ACL-Access List

Access List:

        It is used for filtering or blocking IP address.There are three types of access lists

1.       Standard Access List

                    It provides packet based filtering.Standard access list number range from 1-99.It is configured on destination router.

Configuration:

For blocking particular IP: Router(config)# access-list  <acl num> deny  host <ip address>

For blocking entire networks:  Router(config)# access-list  <acl num> deny  <source ip>

Router(config) access-list <acl num> permit any

Applying to interface: router(config) interface f0/0

Router(config-if)# ip access-group <acl num> in/out –it changes according to the scenario.

2.       Extended Access List:

              Number range from 100-199 and it provides protocol based filtering.we can configure ACL in source router or destination router but better on source router.By configuring extended ACL we can block communication from an IP to IP,network,ip to network,network to IP.

Configuration:

For blocking telnet and protocol

     Router(config)# access-list <acl num> deny <protocol> <source ip> <destination ip> eq <port num>

Ping blocking:

Router(config)# access-list 101 deny ICMP host<ip address> host<destination ip address>

Router(config)# access-list 101 permit ip any any

Applying to interface:

Router(config)# interface f0/0

Router(config-if)# ip access-group <acl num> in

3.       Extended Access list:

Router(config)# ip access-list extended “name”

Router(config-ext-nacl)# deny ip  host <source IP>host<destination IP>

Hybrid Routing

Hybrid Routing

         Protocol  used in hybrid routing is EIGRP.[Enhance Interior Gateway Protocol].It is a cisco proprietory protocol.

Algorithm:

      EIGRP is using dual algorithm.updates are multicasted.Multicasting address is 224.0.0.10.updates are even triggered. maximum hop count is 255.but default value is 100.it ia classless protocol.metric of EIGRP is composit metric.EIGRP maintaining tables are

1.       Neighbour Table

2.       Topology Table

3.       Routing Table

Syntax:

Router(config)# Router eigrp <as number>

[Autonomous Number range is 1-65,535- as number can give any number between 1-65,535

Different as number in different router will not communicate,same as number in different router will only communicate.]

Router(config-router)# network network id

Router(config-router)# exit

[Network id should be  give directly conneted networks]

In this scenario configuration is.

Router1(config)# router eigrp 1

Router(config-router)#  network  192.168.10.0

Router(config-router)#  network  10.0.0.0

Router(config-router)#  exit

Router2(config)  router eigrp 1

Router(config-router)#  network 192.168.10.0

Router(config-router)#  network 192.168.20.0

Router(config-router)#  network 20.0.0.0

Router3(config) router eigrp 1

Router(config-router)#  network 192.168.20.0

Router(config-router)#  network 30.0.0.0

Router(config-router)#  exit

Link Stste Routing:

Link Stste Routing:

OSPF – Open shortest path first

1.       Classless routing protocol

2.       Algorithtm used is ospf algorithm

3.       Unlimited hop count

4.       Updates are multicasted

5.       Multicasting address is 224.0.0.5 /224.0.0.6

6.       Event triggerd updates

7.       Updates are incremented

8.       Metric is cost of the link ie. 100/bandwidth

LSA

  Link state advertise are signals or building blocks to create LSDB – Link state database

Syntax:

Router(config) # router ospf  <1-65,535> -can give any number between this.

Router(config-router)# network network id  wildcadmask  area 0

[Wildcadmask = universal broadcast id –subnet mask

Wildcad mask =255.255.255.255 -

                            255.255.255.0 [ class c]

                             0.0.0.255]

[ Network id should be give directly connected networks ]

In this scenario configuration is.

Router1(config) router ospf  100

Router(config-router) network 192.168.10.0  0.0.0.255  area 0

Router(config-router) network 10.0.0.0  0.255.255.255 area 0

Router(config-router) exit.

Router2(config)  router ospf 100

Router(config-router) network 192.168.10.0  0.0.0.255 area 0

Router(config-router) network 192.168.20.0  0.0.0.255 area 0

Router(config-router) network 20.0.0.0  0.255.255.255 area 0

Router(config-router) exit.

Router3(config)# roter ospf 0

Router(config-router) netwok 192.168.20.0  0.0.0.255  area 0

Router(config-router)network 30.0.0.0  0.0.0.255  area 0

Router(config-router) exit.

                        

Dynamic Routing

Dynamic  Routing

     -routing is done by protocol

Distance vector routing:

                Protocol  used in DVR is routing information protocol.it has two versions

-RIP version 1

-Rip version 2

RIP version 1:

    It is a classfull routing protocol that is support only FLSM and does not support VLSM.

Belmanford algorithm is used in RIP version 1.

                                                                       If we are using rip version 1 updates are broadcasted  one to all.Broadcasting Id is the universal broadcast ID 255.255.255.255. Maximum hop count is 15.

Metric:

    It means the best part to reach from source to destination.Metric of a RIP is hop count.

RIP Version 2:

           RIP version 2 is a classless Routing protocol  and it support VLSM.maximum RIP version hop count is 15.AD value is 120 and updates are multicasted.multicast range of RIP version IP is 224.0.0.9

Configuration of RIP version 1:

Router(config)# router rip  -press enter

Router(config-router)# network  <network id>

Router(config-router)# exit

Configuration of RIP version 2:

Router(config)# router rip

Router(config-router)# version 2

Router(config-router)# network <network id>

Router(config-router)# exit

                             Network id we have to give directly connected networks in a router,which we configure.

Configuration of this scenario:

Router1(config)# router rip 

Router(config-router)# network  192.168.10.0

Router(config-router)# network 10.0.0.0

Router(config-router)#  exit.

Router2(config)# router rip 

Router2(config-router)# network 192.168.10.0

Router2(config-router)# network 20.0.0.0

 Router(config-router)#exit.