Capture RIP v2 Multicast Updates in GNS3 Using Wireshark

Nerd Cafe | نرد کافه

RIP v1 vs RIP v2 Comparison Table

Aspect	RIP v1	RIP v2
Routing Type	Distance Vector	Distance Vector
Standard	RFC 1058	RFC 2453
Metric	Hop Count	Hop Count
Maximum Hop Count	15	15
Hop Count 16	Infinite (unreachable)	Infinite (unreachable)
Routing Updates	Full table	Full table
Update Interval	Every 30 seconds	Every 30 seconds
Transport Protocol	UDP	UDP
UDP Port	520	520
Addressing Type	Classful	Classless
Subnet Mask in Updates	❌ Not included	✅ Included
VLSM Support	❌ No	✅ Yes
CIDR Support	❌ No	✅ Yes
Summarization	Automatic only	Automatic & Manual
Network Advertisement	Broadcast (255.255.255.255)	Multicast (224.0.0.9)
Bandwidth Usage	High (broadcast)	Lower (multicast)
Authentication	❌ None	✅ Plain text & MD5
Security Level	Low	Higher
Route Tagging	❌ No	✅ Yes
Next-Hop Field	❌ No	✅ Yes
Compatibility	Older devices	Modern devices
Loop Prevention	Split horizon, route poisoning	Split horizon, route poisoning
Convergence Speed	Slow	Faster than v1
Scalability	Very limited	Limited (but better than v1)
Administrative Distance	120	120
Default Behavior	Auto-summary enabled	Auto-summary enabled (can disable)
Configuration Complexity	Very simple	Slightly more complex
Use Case	Small legacy networks	Small to medium networks
Current Usage	Obsolete	Rare but still used

Key Takeaways (Easy to Remember)

• RIP v1 = Classful + No security

• RIP v2 = Classless + Secure + Efficient

• Both are slow and not scalable, compared to OSPF or EIGRP

RIPv2 Configuration & Analysis Tutorial

1. Network Topology Understanding

2. Configuration Steps for R1

R1> enable
R1# configure terminal
R1(config)# router rip
R1(config-router)# version 2
R1(config-router)# network 10.0.0.0
R1(config-router)# network 192.168.1.0
R1(config-router)# no auto-summary
R1(config-router)# exit
R1(config)# exit
R1# copy running-config startup-config

3. Configuration Steps for R2

R2> enable
R2# configure terminal
R2(config)# router rip
R2(config-router)# version 2
R2(config-router)# network 10.0.0.0
R2(config-router)# network 192.168.2.0
R2(config-router)# no auto-summary
R2(config-router)# exit
R2(config)# exit
R2# copy running-config startup-config

4. Verification Commands

On R1:

R1# show ip route
R1# show ip protocols
R1# debug ip rip

On R2:

R2# show ip route
R2# show ip protocols
R2# debug ip rip

5. Analyzing the Capture

From Wireshark/RIP packet details:

• Multicast address: 224.0.0.9 (standard for RIPv2)

• Port: 520 (RIP)

• Updates sent every ~30 seconds (visible in Time column)

• Example route in update:

IP Address: 192.168.1.0
Netmask: 255.255.255.0
Next Hop: 0.0.0.0 (means "advertise yourself as next hop")
Metric: 1 (directly connected)

💖 Support Our Work

If you find this post helpful and would like to support my work, you can send a donation via TRC-20 (USDT). Your contributions help us keep creating and sharing more valuable content.

TRC-20 Address: TAAVVf9ZxUpbyvTa6Gd5SGPmctBdy4PQwf

Thank you for your generosity! 🙏

Keywords

RIPv2, IP routing, network configuration, subnetting, router CLI, Wireshark analysis, multicast 224.0.0.9, routing protocol, convergence, interface configuration, network topology, packet capture, Cisco commands, metric, next-hop, link-state, route advertisement, debug ip rip, show ip route, network simulation, nerd cafe , نرد کافه

Channel Overview

🌐 Website: www.nerd-cafe.ir

📺 YouTube: @nerd-cafe

🎥 Aparat: nerd_cafe

📌 Pinterest: nerd_cafe

📱 Telegram: @nerd_cafe

📝 Blog: Nerd Café on Virgool

💻 GitHub: nerd-cafe