ccna written exam

ccna written exam

LSP Version=0 length in words=10 687 2 10.1.23.3 [MPLS: Labels 305/403/505 Exp 0] 8 msec 4 msec 4 msec Let's look at the picture. If R1 to R6 want to establish a TE tunnel , which is the optimal path, and the bandwidth requirement is 30Mbps , what is the calculation process? First of all, thanks to the flooding of link state information in the zone, " OSPF or IS-IS for MPLS TE extensions ", Neighbor discovery is performed by means of the Hello packet of UDP . The source and destination port of this Hello packet are both UDP646 . Is-type command such as is-type level-1 Local Circuit ID Local circuit ID is a link identifier. The identity of this circuit is assigned by the router that sent the Hello PDU and is unique on the interface of the router. At the other end of the point-to-point link , the local circuit ID in the Hello message may or may not be the same value. Next hop 10.1.12.2, FastEthernet0/0 valid cached adjacency Next , take a look at the Tunnel on R1 : *Aug 18 11:31:44.598: Default change threshold (bandwidth occupancy): Outgoing interface i L2 Router isis ! And in R2 , the label package is pushed into a new layer of labels, the outer label is assigned by R3 ,ccna written exam, and the inner label is assigned by R4 . The external route is not carried in the LSP . LAN on the MAC or the X.25 , FR or ATM in the virtual circuit ID 0x4F65 By selection ( level2 routing) Interface Tunnel0 Its ingress and exgress LSRs Is-type level-1 metric-style wide !! Use the dynamic calculation method to establish the tunnel PATH Ip address 4.4.4.4 255.255.255.255 Ip address 2.2.2.2 255.255.255.255 R1#show mpls traffic-eng tunnels protection The configuration of R2 is as follows: ISO10589 OSPF Router with ID (1.1.1.1) (Process ID 1) Reservable Bandwidth[2]: The boundary of the area is on the link Interface eth 0/0 10.1.23.0/24 Admin: up Tspec: ave rate=60000 kbits, burst=1000 bytes, peak rate=60000 kbits RSVP Resv Info: Now, shut down the e0/1 port of R2 . Interface loopback0 Next, add a PVC between R2 and R3 : ! The configuration of R1 is as follows: Overload-bit This state has three values: down , init , up This time, we do some tests, R1 configuration area-password and R2 are not the same configuration. In this way , although the neighbor relationship can be established for R1 and R2 , they cannot learn the route of the other party, because neither party recognizes the LSPs . When a router receives a tagged message, it searches in the LFIB table. The related matching entries in the LFIB table have outbound actions or labels for the inbound tag, and next hop information. . ! Look at the routing table on R3 : One is a Point-to-Point IS to IS hello PDU . Tunnel mpls traffic-eng path-option protect 10 explicit name R2R3R4 Physical Bandwidth: Physical bandwidth of the 100000 kbits/sec !! interface RFC 3567 ! Since OSPF is inherently designed to support IP routing, and IS-IS still has some vendors' devices that are not perfectly supported, OSPF is still preferred for a significant portion of the network . However , interest in using integrated IS-IS for IP routing is increasing, and most ISPs in Europe use IS-IS . Many new ISPs are also considering deploying IS-IS . Mpls traffic-eng tunnels ip rsvp bandwidth Interface fas0/0 OSI terminology 10.1.34.0 [115/20] via 10.1.23.3, Serial1/0 Set-overload-bit suppress interlevel redistribute connected level-1 Protocols support The configuration of R1 is as follows: ! Name: R1_t0 Status: Ip router isis PSNP Interface Loopback0 After the above configuration is complete, R2 will send LDP through the tunnel that has been established and reaches R4 . Note that the tunnel must activate the MPLS IP. Overview of the label assignment process The configuration of RouterA is as follows: 1174 Peer LDP Ident: 3.3.3.3:0; Local LDP Ident 1.1.1.1:0 10.1.23.0/24 Network Service Access Point . It is a conceptual point on the boundary between the network layer and the transport layer. It is the location where the OSI network layer serves the transport layer. Each transport layer entity is assigned a unique NASP address. Record Route: 2.2.2.2(200) 4.4.4.4(403) Mpls traffic-eng tunnels ip rsvp bandwidth MPLS is a forwarding technology based on packet labeling R2#show ip ospf database router self-originate The configuration of R5 is as follows: 10.1.12.1 TE metric: 1 Activate RRO with the following configuration: The POP will only pop the top label header. The packet forwarded by this action can be an IP packet or an MPLS label packet. The target network segment involved in MPLS is the same as traditional IP forwarding. 1.1.1.1 Name: R1_t0 Status: Interface fa0/0 mpls ip Network 10.1.45.4 0.0.0.0 area 0 Router router The routing table of R2 is as follows (omit direct route): 10.1.23.2 R1_t0 0x00000037 Local Comment !! Re-release the local direct loopback 2.2.2.0/24 to level1 Therefore, R1 will only use R4 's label mapping for 3.3.3.3 , that is, use label 404 to send the label packet to 3.3.3.3 . Basic Ip address 3.3.3.3 255.255.255.255 Mpls traffic-eng tunnels mpls ip Packets with the same processing mode according to the process or IP DSCP field Two routers to establish LDP neighbors, to ensure that the parties to the other side of the LDP ID triple up Prior LSP: Network 10.1.23.2 0.0.0.0 area 0 mpls traffic-eng router-id Loopback0 mpls traffic-eng area 0 *Aug 18 09:06:07.919: SENDER_TEMPLATE type 7 length 12: Meet the FIB , LIB , and LFIB tables Therefore, the MPLS VPN environment, if we MPLS VPN Backbone inherent R1 to R5 establish a TE the Tunnel , is not Status Router isis R3.00-00 Src 2.2.2.2, Dst 4.4.4.4, Tun_Id 0, Tun_Instance 6 RSVP Path Info: Ip address 10.1.24.2 255.255.255.0 Explicit Route: 10.1.45.5 5.5.5.5 Fa0/0 L1/L2 router re-releases external routes into IS-IS ( to level1 ) !! Cross-regional words must use loose next hop Neighbor 5.5.5.5 send-community extended exit-address-family ISO10589 ISIS for NBMA support network is still flawed, as in the previous experiment demonstrates, if it is run on a Frame Relay main interfaces ISIS , or P2MP run on sub-interfaces ISIS , then you must ask PVC full-mesh, otherwise, the route study Not normal, but even if the PVC is fully interconnected, there are hidden dangers. If a PVC fails, routing will still have problems. Mpls traffic-eng tunnels ip rsvp bandwidth Type 2 length 36: Signalling: connected Interface FastEthernet0/0 The basic feature of MPLS is that all packets are tagged, so it is impossible to distribute labels such as OSPF , EIGRP , RIP , and ISIS . Then you need a new protocol that is independent of all routing protocols and can be used in conjunction with all IGPs . LDP is one such protocol. Of course, BGP is because it carries external routes. Therefore, it is more effective and even perfect to use BGP itself to distribute tags. Therefore, BGP can implement multiple protocols, and the impact of using it to distribute tag information is very small. And BGP is the only protocol that distributes prefixes between AS autonomous systems.