Name: Jiang Shuming
Student ID: 201821121109
Class: calculated 1814
1 Purpose
- Understanding and establish RIP routing table updates
- RIP feeling bad news travels slow
2 Experimental content
Use Packet Tracer, properly configure network parameters, use the command to view and analyze RIP routing information.
- Establish a network topology
- Configuration parameters
- Analysis of RIP routing information
3. The test report
3.1 Establish a network topology
Network topology as shown below:
3.2 Configuration Parameters
-
PC0 ip address:192.168.1.109
Route0 Fa0/0 ip address:192.168.1.110
Route0 Fa0/1 ip address:192.168.2.109
Route1 Fa0/0 ip address:192.168.2.110
Route1 Fa0/1 ip address:192.168.3.109
PC1 ip address:192.168.3.110 - Route0 router configuration, and comprising an interface configured RIP
Configure and activate port
• Router> enable # to enter the privileged EXEC mode
• Router # configure terminal # enter the global configuration mode
• Router (config) #hostname R # router name is configured to R
Configuring Fa0 / 0 interface
• R(config)#interface Fa0/0
• R(config-if)#ip address 192.168.1.110 255.255.255.0
• R (config-if) #no shutdown # interface to activate
After activation of the interface, an arrow found Fa0 / 0 interface from red to green
The same method of activating Fa0 / 1 Interface
At this point, the router interface is configured Route0 completed, followed by the same manner as the router interface to the final result shown in FIG Route2
Next, configure RIP
Enable Dynamic Routing
• R(conf)# router rip
• R (conf) #version 2 version rip 2
• R (conf) #no auto-summary to turn off automatic route summarization
Specify Network
• R(conf)#network 192.168.1.0
• R(conf)#network 192.168.2.0
The same method of configuring Route1, so far, RIP has been configured
3.3 Testing Network Connectivity
In PC1, PING PC2, the whole link connectivity test given screenshot below.
The results showed that normal communication can
The results show ip route network is displayed in the normal communication:
The results show ip interface brief show normal communication network:
3.4 understand RIP routing table to establish and update
- View information routing process
show ip protocols
routering protocols is "rip" routing protocol is rip protocol
Sending updates every 30 seconds, rip to discover and maintain routes, the default broadcast every 30 seconds once the routing table through regular broadcast the entire routing table.
next due in the next 14 seconds once updated after 14 seconds
Invalid after 180 seconds 180 Miao did not receive routing information considered out of the question
flushed after 240 seconds after 240 refresh
Outgoing update filter list for all interfaces is an access list with a direction
Incoming update filter list for all interfaces is used for inbound access lists
Redistributing: rip Publishing Protocol: RIP
Default version control: send version 2, receive 2 Default Control Version: Version 2 transmitted, received version 2
Maximum path: 4: 4 routing protocol can support equivalent path
- Check in routing table
show ip route
C- attached, static S-, R- Routing Information Protocol, M- movement, B- Border Gateway Protocol;
192.168.1.0/24 variable subnet, Subnet 2, two masks;
192.168.1.0/24 directly connection. - View RIP send and receive messages
debug ip rip
RIP: sending v2 update to 224.0.0.9 via FastEthernet0 / 0; // send updates via port version 2 0/0
RIP: build update entries; // create an updated entry
RIP: receivee v2 update from 192.168.2.110 on FastEthernet0 / 1; // update the version received from the port 2 0/1
4. appreciated RIP message travels slowly
Command shutdownClose Route0 Interface Fa0 / 0. In Route0 View RIP routing update information debug ip rip, and a brief analysis of Route0 routing table is how to re-converge.
When the network fails, the need to go through a long period of time in order to transmit this information to all routers. Example: Suppose there are three routers, routers and three have established their own routing table, router R1 and the network is now connected to line 1 and the dyed short open. After the discovery router R1, the distance to the web 1 to 16, and this information is sent to router R2. Since the router R2 R3 information sent is: "the distance R2 to the web 1 through 2", then this program is updated to R2 "R3 distance to web 1 through 3", issued to R3. R2 R3 and then distributed to the information: "the distance of the web 1 through 4." When this has been to increase the distance to 16, R2 and R3 to know 1 network is not reachable. This feature is called: Good news travels faster, but bad news travels slowly. Network failure like this propagation time is often takes a long time, therefore, the RIP Bad news slowly.
5. expansion
(1) by PING crawl ICMP packet, and analysis.
TYPE: 0x08; (echo request) type, accounts for a byte identifying the type of ICMP packet, the ICMP packet type value point of view can be divided into two categories. The first category is the value of error packets 1 to 127, category 2 is 128 or more values of information packets;
CODE: 0x00; code representing a byte identification code corresponding to the ICMP message. It identifies the type field together with the detailed type of ICMP packet;
CHECKSUM: checksum, which is the entire datagram ICMP checksum including ICMP data packet including the parts and to verify the message during transmission whether an error has occurred;
(2) questions
RIP working process is like?
Initial state : When the RIP process started early, processes send RIP routing information between the request and response messages, interact with neighbors on the interface is declared;
Building Routing Table : After collecting routing information of the neighbor's neighbors, counting entries based routing update;
Maintaining the routing table : after the initial routing table is complete, the start of each route start a separate update cycle timer, send a routing update in a cycle, while updating and triggered update routing information and update the aging cycle according to received. Upon receipt of such a route of entry for routing updates (16 non-jump), to reset the aging timer for this route.
Aging routing table entries : If you still have not received within the time a neighbor aging timer from the routing update, the route entry will be set up for the jump is not 16, and starts garbage collection timer;
Garbage Collection entry : router garbage collection will be sent before the timer expires in the network route cost value = 16 hops is unreachable information, clear the error routing information network;
Delete routing table entries : When the garbage collection timer expires, this entry routing information will be completely removed from the RIP database.