Basic Serial Interface Config and Verification

Basic Serial Interface Config and Verification

1. 1. Connectors etc

   • 1. V.35 – Supports speeds of 2.048 Mbps using a rectangular connector
   • 2. DB-60 – A 60-pin connector (also known as a Cisco 5-in-1 connector) that is supported on several Cisco router models
   • 3. Smart Serial – A “high-density” connector that allows a WAN interface Card (WIC) to have two serial connections instead of just one
   • 4. EIA/TIA-232 – A 25- pin D-connector that supports speeds of 64 kbps for short distances
   • 5. Data-Communication Equipment (DCE) – The end of a serial cable that provides clocking
   • 6. Data-Terminal Equipment (DTE) – The end of the serial cable that receives clocking
   • 7. High-Level Data Link Control (HDLC) – The default Layer 2 protocol used by Cisco routers on serial interfaces. Cisco uses their own proprietary version of HDLC
     • Able to support multiple protocols
     • R1#show controllers s0/0 R1(config)#int s0/0 R1(config-if)#ip address 10.1.1.1 255.255.255.252 R1(config-if)#bandwidth 500 R1(config-if)#no shutdown
     • R2(config)#int s0 R2(config-if)#ip address 10.1.1.2 255.255.255.252 R2(config-if)#bandwidth 500 R2(config-if)#clock rate 500000 R2(config-if)#no shutdown

2. 2. Configuring and verifying PPP

   • 1. A Layer 2 encapsulation commonly used on leased lines, which supports authentication, compression, error checking and correction, and a logical multilink interface
   • 2. Link Control Protocol (LCP) – A protocol used by PPP to setup, maintain, and teardown a connection
   • 3. Network Control Protocols (NCP) – The protocols used to negotiate the configuration of protocols being transmitted over a PPP link
   • 4. Compression
   • 5. Error Detection and Correction
   • 6. Multiple Link Support
   • 7. Authentication
     • Password Authentication Protocol (PAP) – A type of authentication used by PPP that only performs one-way authentication and send the PAP password across the network in clear text
     • Challenge-Handshake Authentication Protocol (CHAP) – A type of authentication used by PPP that performs two-way authentication and sends a hash of the CHAP password over the network, instead of the actual password
   • R1(config)#int s1/0 R1(config-if)#encap ppp R1(config-if)#int s1/1 R1(config-if)#encap ppp
   • R2(config)#int s1/0 R2(config-if)#encap ppp R2(config-if)#int s1/1 R2(config-if)#encap ppp
   • R1(config)#username papuser password pappass R1(config)#int s1/0 R1(config-if)#ppp authentication pap R2(config)#int s1/0 R2(config-if)#ppp pap sent-username papuser password pappass
   • R1(config)#username R2 password chappass R1(config)#int s1/1 R1(config-if)#ppp authentication chap
   • R2(config)#username R1 password chappass R2(config#int s1/1 R2(config-if)ppp authentication chap
   • R1(config)#int s 1/0 R1(config-if)#compress stack (compresses data) Do the same on Router 2
   • R1(config)#int s1/1 R1(config-if)#ppp reliable-link (sets up error checking) Do the same on Router 2
   • R1(config)#int multilink 1 R1(config-if)#ip address 10.1.1.1 255.255.255.252 R1(config-if)#ppp multilink R1(config-if)#int s1/0 R1(config-if)#no ip address R1(config-if)#ppp multilink group 1 R1(config-if)#int s1/1 R1(config-if)#no ip address R1(config-if)#ppp multilink group 1 Do the same on router 2

3. 3. Configuring and verifying Frame Relay

   • 1. PVC Status: Active – The connection between your router and the far router is good
   • 2. PVC Status: Inactive – The connection is good between the local router and the Frame Relay switch, but not between the Frame Relay switch and the far-end router
   • 3. PVC Status: Deleted – The connection is not good between the local router and the Frame Relay switch
   • 4. Inverse ARP – Allows a Frame Relay router to determine the Layer 3 address at the far-end of a DLCI
   • 5. Subinterfaces – Logical divisions of a physical interface, each of which can belong to a separate subnet
     • Point-to-Point
       • Associated with a single DLCI
     • Multipoint (Point-to-Multipoint)
       • Associated with one or more DLCIs
   • 6. Command to disable Split Horizon for EIGRP
     • HQ(config-subif)#no ip split-horizon eigrp AS_NUMBER
   • 7. Command to configure OSPF Network Type
     • HQ(config-subif)#ip ospf network point-to-point BR1(config-if)#ip ospf network point-to-point BR2(config-if)#ip ospf network point-to-point
   • HQ(config)#int s1/0 HQ(config-if)#encapsulation frame-relay HQ(config-if)#frame-relay lmi-type ansi Do the same on the other routers
   • HQ#show frame-relay pvc HQ#show frame map (shows IPs) BR2(config)#int s1/0 BR2(config-if)#frame-relay map ip 10.1.1.2 (IP of BR1)301(DLCI) broadcast Do the same on router BR1 Replace dynamically learned mappings with static mappings because static mapping turns off Inverse ARP

4. 4. Configuring and verifying PPoE

   • Point-to-point Protocol over Ethernet (PPPoE) – A technology where PPP frames are encapsulated inside of Ethernet frames, thus allowing Ethernet devices to take advantage of PPP features (e.g. authentication)