Intermediate System - Intermediate System -- Part 1

ISIS was originally designed for Open System Interconnect (OSI) protocol Suite. The Connectionless Network Service (CLNS) is been used & introduced by OSI.

The form of running on Cisco routers is Integrated IS-IS, Which supports both CLNP and IP.

ISIS Terminology

An OSI domain is very much like a domain with the other routing protocols you've studied – it's a segment of a network that's under a common administrative control. An area is a logical segment of the network that is composed of contiguous router and their connecting data links.

These are logical entities, but there are two physical bodies as well. A host is an End system (ES). An Intermediate System (IS) is a router. Not a group of routers, a single router.

ISIS uses a two level hierarchy, allowing a large domain to be subdivided into areas

An L1/L2 router can act as an L1 and L2 router at the same time. An L1/L2 router can have neighbor in separates ISIS areas. The L1/L2 router will have two separate database – one for L1 routes and another for L2 routes

L1/L2 is the default setting for Cisco routers running ISIS

In Upcomming parts will digg further.

ISIS has three type of router: - Level 1 [L1], Level 2[L2] and L1/L2 

Level -1

L1 routers are contained in a single area, and are connected to other areas by an L1/L2 router. The L1 uses the L1/L2 router as a default gateway to reach destination contained in other areas.

Level - 1/2

An L1/L2 router can act as an L1 and L2 router at the same time. An L1/L2 router can have neighbor in separates ISIS areas. The L1/L2 router will have two separate database – one for L1 routes and another for L2 routes

L1/L2 is the default setting for Cisco routers running ISIS

CCIE Service Provider Lab Equipment and Operating System v3.0

The practical exam tests any feature that can be configured on the equipment and the IOS versions indicated in the document below. You may see more recent IOS versions installed in the lab, but you will not be tested on the new features of a release unless indicated below.


Lab Equipment

• Cisco XR12000 Series Routers
• Cisco 7200/7600 Series equivalent Routers (Using Simulator)
• Cisco ME3400E Series Switches

Software Versions

• XR12000 routers running IOS-XR Software Version 3.9.1
• 7200/7600 routers running IOS Software Version 12.2-33 SR
• ME3400E switches running IOS Software Version 12.2-54 SE

CCIE Service Provider Lab Exam v3.0 Checklist

1. Implement, Optimize and Troubleshoot Core IP Technologies



1.1. Packet over SONET
1.1.1. Cisco HDLC encapsulation
1.1.2. PPP encapsulation
1.1.3. Frame Relay encapsulation
1.1.4. Maximum transmission unit (MTU)
1.1.5. Cyclic redundancy check (CRC)
1.1.6. Keepalive timer
1.1.7. Frame Relay DLCI on point to point sub-interface
1.1.8. SONET Controller
1.1.9. POS channel



1.2. GE/10GE in the Core

1.2.1. MAC accounting
1.2.2. Speed
1.2.3. Duplex mode
1.2.4. Carrier Delay
1.2.5. MTU
1.2.6. Flow control
1.2.7. 802.1Q VLAN sub-interface



1.3. IGP routing

1.3.1. IS-IS Multi topology
1.3.2. IS-IS Multi instance
1.3.2. IS-IS System Type
1.3.3. IS-IS Metric Type
1.3.4. IS-IS Area
1.3.5. IS-IS Designated Intermediate Systems
1.3.6. IS-IS Interface Circuit Type
1.3.7. IS-IS Interface Metric
1.3.8. IS-IS Retransmission Throttle Interval
1.3.9. IS-IS LSP Interval and Lifetime
1.3.10. IS-IS Point-to-point Adjacency over Broadcast Media
1.3.11. IS-IS route leaking
1.3.12. OSPF multi instance
1.3.13. OSPF Multi Areas
1.3.14. OSPF router ID
1.3.15. OSPF over different physical network
1.3.16. OSPF neighbor
1.3.17. OSPF interface cost
1.3.18. OPSF designated router
1.3.19. OSPFv3 support for IPv6
1.3.20. EIGRP multi instance
1.3.21. EIGRP Autonomous System Configuration
1.3.22. EIGRP Cost Metrics
1.3.23. EIGRP Equal and Unequal Cost Load Balancing
1.3.24. EIGRP support for IPv6
1.3.25. RIP v2
1.3.26. RIP support for IPv6
1.3.27. Redistribution between OSPF,IS-IS and EIGRP
1.3.28. Redistribution of Directly connected routes
1.3.29. Redistribution of Static routes
1.3.30. Route summary
1.3.31. IOS-XR routing policy language (RPL)
1.3.32. Routing policy using route-map



1.4. MPLS and LDP


1.4.1. IP CEF
1.4.2. LDP router ID
1.4.3. LDP interface
1.4.4. LDP neighbor auto discovery
1.4.5. MPLS MTU
1.4.6. MPLS LDP Static label
1.4.7. MPLS LDP—Local Label Allocation Filtering
1.4.8. MPLS LDP-IGP synchronization
1.4.9. MPLS LDP Inbound/outbound Label Binding Filtering



1.5. MPLS Traffic Engineering

1.5.1. IS-IS support for MPLS TE
1.5.2. OSPF support for MPLS TE
1.5.3. RSVP for MPLS TE
1.5.4. MPLS TE tunnel setup
1.5.5. MPLS TE Tunnel bandwidth
1.5.6. MPLS TE Automatic Bandwidth
1.5.7. MPLS TE Static route
1.5.8. MPLS TE Auto route
1.5.9. MPLS TE Policy route
1.5.10. MPLS TE Forwarding adjacency
1.5.11. MPLS TE Metric
1.5.12. MPLS TE LSP attributes
1.5.13. MPLS TE Class-based Tunnel selection
1.5.14. MPLS TE Policy-based Tunnel selection
1.5.15. MPLS Pseudowire Tunnel Selection
1.5.16. Point to multi point ( P2MP) MPLS TE
1.5.17. Inter-Domain MPLS TE
1.5.18. Inter-Area MPLS TE



1.6. BGP


1.6.1. IBGP IPv4/IPv6 Peering
1.6.2. EBGP IPv4/IPv6 Peering
1.6.3. EBGP IPv4/IPv6 multi hop peering
1.6.4. BGP IPv4/IPv6 routes advertising
1.6.5. EBGP IPv4/IPv6 peering using local-AS
1.6.6. EBGP IPv4/IPv6 peering using AS-override
1.6.7. BGP IPv4/IPv6 using private AS number
1.6.8. Dual AS configuration for Network AS migration
1.6.9. BGP Next-Hop
1.6.10. BGP Weight
1.6.11. BGP Local Preference
1.6.12. BGP MED
1.6.13. BGP Origin
1.6.14. BGP Communites
1.6.15. BGP Confederation
1.6.16. BGP Router reflector
1.6.17. BGP Cluster list
1.6.18. BGP Peer Groups
1.6.19. BGP Synchronization
1.6.20. BGP Aggregation
1.6.21. BGP Conditional Advertising
1.6.22. BGP Routing policy
1.6.23. Redistributing IGP, static and connected route into BGP
1.6.24. BGP Multi-path Load Sharing
1.6.25. BGP Link Bandwidth



1.7. Multicast

1.7.1. IPv4/IPv6 Multicast addressing
1.7.2. IPv4/IPv6 Multicast routing
1.7.3. PIM Sparse Mode for IPv4/IPv6
1.7.4. IGMP V2/V3
1.7.5. IPV6 Multicast Listener Discover (MLD)
1.7.6. PIM Source Specific Multicast (SSM) for IPv4/IPv6
1.7.7. Multicast Rate-limiting
1.7.8. PIM Bidirectional (BiDir)
1.7.9. PIM Static RP
1.7.10. PIM Bootstrap Router (BSR)
1.7.11. PIM Auto RP
1.7.12. PIM Anycast RP
1.7.13. Multicast Administrative Boundaries
1.7.14. MSDP
1.7.15. MP-BGP peer for Multicast
1.7.16. MP-BGP Multicast route advertising


1.8. High Availability

1.8.1. NSF/SSO for IGP routing
1.8.2. NSF/SSO for BGP routing
1.8.3. NSF/SSO for LDP, TE, Multicast
1.8.4. HSRP, VRRP, GLBP
1.8.5. Graceful Restart
1.8.6. Control Plane Policing (CPP)
1.8.7. Bidirectional forwarding detection (BFD)
1.8.8. IP event dampening
1.8.9. IGP Fast Re-route
1.8.10. MPLS TE Fast Re-route (FRR)
1.8.11. Link Protection using MPLS-TE
1.8.12. Node Production using MPLS-TE
1.8.13. Embedded event management (EEM)


1.9. Convergence

1.9.1. IS-IS fast convergence
1.9.2. IS-IS to utilize the Overload Bit
1.9.3. OSPF fast convergence
1.9.4. BGP fast convergence
1.9.5. BGP Route Dampening
1.9.6. BGP Fast Peering Session Deactivation
1.9.7. BGP Prefix Independent Convergence (PIC)
1.9.8. BGP next hop tracking
1.9.9. BGP address tracking filter
1.9.10. BGP path MTU discovery
1.9.11. IP fast reroute (IPFRR)
1.9.12. Multicast-only Fast Re-Route (MoFRR)
1.9.13. MPLS LDP convergence


1.10. SP QoS

1.10.1. Marking using DSCP, IP precedence and CoS
1.10.2. Priority Queuing
1.10.3. Custom Queuing
1.10.4. Weighted Fair Queuing
1.10.5. WRED
1.10.6. Policing
1.10.7. Class-based Weighted Faire Queuing (CB-WFQ)
1.10.8. Low-Latency Queuing (LLQ)
1.10.9. Random-Detect using MQC
1.10.10. NBAR for QoS
1.10.11. MPLS EXP
1.10.12. Differentiated Services Traffic Engineering (DS-TE)
1.10.13. Maximum Allocation Model (MAM)
1.10.14. Russian Dolls Model (RDM)
1.10.15. Class-Based Tunnel Selection: CBTS
1.10.16. Policy-based Tunnel Selection: PBTS


1.11. Security in core

1.11.1. Standard Access-lists
1.11.2. Extended Access-lists
1.11.3. Routing Protocol Authentication for RIP V2
1.11.4. Routing Protocol Authentication for EIGRP
1.11.5. Routing Protocol Authentication for OSPF
1.11.6. Routing Protocol Authentication for IS-IS
1.11.7. Routing Protocol Authentication for BGP
1.11.8. BGP TTL Security Check
1.11.9. Infrastructure ACL
1.11.10. Anti Fragment Attacks
1.11.11. Filtering RFC 1918 Routes
1.11.12. uRPF for Anti-Spoofinng
1.11.13. Selective packet discard (SPD)
1.11.14. LDP authentication
1.11.15. Remote triggered black hole (RTBH)
1.11.16. NTP
1.11.17. Attack mitigation
1.11.18. SNMP Management
1.11.19. IP packet Accounting
1.11.20. Syslog



2. Implement, Optimize and Troubleshoot Edge/Access Technologies

2.1. FE/GE and Ethernet Trunk

2.1.1. Ethernet channel
2.1.2. Virtual Trunking Protocol (VTP)
2.1.3. Spanning Tree Protocol (STP)
2.1.4. 802.1Q VLAN
2.1.5. 802.1QinQ
2.1.6. 802.1ad Provider Bridges (PB)
2.1.7. 802.1ah Provider Backbone Bridge (PBB)
2.1.8. Connectivity Fault Management (CFM)


2.2. Frame-Relay connection

2.2.1. Frame-Relay DLCI
2.2.2. Frame-Relay map
2.2.3. Frame-Relay switching
2.2.4. Frame-Relay multilink
2.2.5. Frame-Relay LMI-Type
2.2.6. PPP over Frame-Relay


2.3. PPP connections

2.3.1. PPP encapsulation
2.3.2. PPP multilink
2.3.3. PPP Multi chassis multilink
2.3.4. PPPoE client
2.3.5. PPPoE server
2.3.6. PPP authentication


3. Implement, Optimize and Troubleshoot Layer 3 VPN

3.1. Intra AS L3 MPLS VPN
3.1.1. MP-IBGP VPNv4/VPNv6 peering
3.1.2. MP-IBGP peering using loopback interface
3.1.3. VPNv4/VPNv6 Route Reflector
3.1.4. VRF definition
3.1.5. Route Distinguisher
3.1.6. Route Target
3.1.7. Route Target import/export
3.1.8. Intra AS MPLS VPNV4/VPNV6 load balancing
3.1.9. SOO Community
3.1.10. PE-CE – RIP V2
3.1.11. PE-CE – IS-IS
3.1.12. PE-CE – OSPF
3.1.13. PE-CE – EBGP
3.1.14. PE-CE – Static Routes
3.1.15. Redistributing dynamic PE-CE routes into VPNv4/VPNv6
3.1.16. Redistributing static PE-CE routes into VPNv4/VPNv6
3.1.17. Redistributing VPN4/VPNv6 routes into PE-CE routing table
3.1.18. Intra-AS MPLS VPN multipath
3.1.19. Intra-AS MPLS VPN path selection


3.2. Inter AS L3 MPLS VPN

3.2.1. MP-EBGP VPNv4/VPNv6 peering using direct interface
3.2.2. MP-EBGP VPNv4/VPNv6 peer using multi-hop interface
3.2.3. MP-EBGP VPNv4/VPNv6 peer between RRs
3.2.4. VPNV4/VPNv6 next-hop unchanged
3.2.5. VPNV4/VPNv6 next-hop self
3.2.6. Multi VRF between ASPEs
3.2.7. Inter-AS MPLS VPNV4/VPNv6 multipath
3.2.8. Route target rewrite
3.2.9. Inter-AS MPLS VPN path selection


3.3. Carrier supporting carrier

3.3.1. MPLS LDP in customer carrier site
3.3.2. EBGPv4 + label between CSC-PE and CSC-CE
3.3.3. IGP + LDP between CSC-PE and CSC-CE
3.3.4. MPLS VPNv4 between customer carrier sites PEs
3.3.5. CSC VPN load balancing
3.3.6. VRF definition in customer carrier site
3.3.7. Customer carrier site PE-CE routing


3.4. VPN Extranet and internet access

3.4.1. MP-BGP VPNv4/VPNv6 Extra-Net
3.4.2. MP-BGP VPNv4/VPNv6 internet access
3.5. VRF service
3.5.1. Multiple VRF
3.5.2. Multiple VRF routing
3.5.3. VRF Selection based on Source IP Address

3.6. Multicast VPN

3.6.1. Default MDT
3.6.2. Data MDT
3.6.3. MP-BGP mdt peering
3.6.4. Multicast routing in VPN site
3.6.5. PM-SM in VPN site
3.6.6. RP in VPN site
3.6.7. Multicast VPN extranet



3.7. GRE L3 VPN

3.7.1. MPLS VPN—L3VPN over GRE


4. Implement, Optimize and Troubleshoot Layer 2 VPN

4.1. AToM
4.1.1. Psuedowire class
4.1.2. Ethernet over MPLS (EoMPLS)
4.1.3. Ethernet VLAN over MPLS
4.1.4. Frame Relay over MPLS (FRoMPLS)
4.1.5. HDLC over MPLS (HDLCoMPLS)
4.1.6. PPP over MPLS (PPPoMPLS)
4.1.7. PWE3 control using LDP
4.1.8. Psuedowire redundancy
4.1.9. AToM interworking
4.1.10. AToM local switching
4.1.11. AToM intra-as support
4.1.12. AToM inter-as support
4.1.13. Traffic Engineering with AToM


4.2. VPLS and Carrier Ethernet

4.2.1. VPLS
4.2.2. H-VPLS
4.2.3. VFI definition
4.2.4. VPLS BGP auto discovery
4.2.5. VLAN attached circuit
4.2.6. QinQ attached circuit
4.2.7. 802.1ad attached circuit
4.2.8. 802.1ah attached circuit
4.2.9. VPLS/H-VPLS redundancy


4.3. L2TPV3 for L2VPN

4.3.1. L2TPv3
4.3.2. L2TPv3 VPN local switching
4.3.3. L2TPv3 VPN interworking
4.4. GRE L2VPN
4.4.1. L2VPN over GRE

5. Implement, Optimize and Troubleshoot Managed Services Traversing the Core


5.1. Managed Voice/Video services traversing the core
5.1.1. Traverse Voice/video packet
5.1.2. Traverse call signal packet
5.2. Managed Security services traversing the core
5.2.1. Traverse IKE packet
5.2.2. Traverse ESP, AH packet
5.2.3. Traverse SSL packet


5.3. Service Level Agreements for managed services

5.3.1. IP SLA sender
5.3.2. IP SLA responder
5.3.3. IP SLA for MPLS VPN
5.3.4. Netflow
5.3.5. Netflow for MPLS
5.3.6. Netflow for Multicast

Why OSPF Neighbors Stuck in Exstart/Exchange State ?

This is the issue that we face some time & really it get hard or will take the entire day to resolve the issue ...

Let us see the most common reason that Why OSPF Neighbor Stuck in Exstart/ Exchange state.

What happen exactly in Exstart/ Exchange State ?

OSPF neighboring routers establish the relation & move forward ... In this state, the neighboring routers establish a master/slave relationship and determine the initial database descriptor (DBD) sequence number to use while exchanging DBD packets. Once

Now below are the reason that why the neighbor stuck in exstart/ exchange state

1]  MTU Mismatch
2] Same router ID on both router.
3] SequenceNumberMismatch
4] BadLSReq

Traffic Engineering with L2TPv3

As previously I had shared the document that show how to configure MPLS Traffic Engineering with Per VRF , But if we ant to have Traffic Engineering with L2 Circuit the how it can possible ?


Traffic Engineering is possible in most of the scenario & with most of the protocol, But only think is that we need to tweak the old technology with new technology to achieve the requirement.

Here the below document shows that how we can do Traffic Engineering with L2tpv3 aka L2Circuit .

Traffic Engineering with L2TPv3
 

OSPF Without Area 0

As we know that in OSPF we need to have Area 0 and also aka Backbone Area. But In MPLS Domain the OSPF Backbone Area term had detached.

Instead of having Backbone Area, In MPLS Domain we have some thing known as Super Back Bone. The Service Provider network is Know as Super Backbone area in MPLS Domain, which replace you traditional OPSF backbone Area.


So as per Traditional OSPF design we supposed to have Area 0 but in MPLS domain Super Back bone area is not associated with any area number. So in MPLS domain OSPF can work without Area 0.

Below Document show that how OSPF is configured without Area 0

OSPF Without Area 0

Ethernet over MPLS

EoMPLS, as specified in the draft-martini allows Layer 2 Ethernet frames to be transported across a Multiprotocol Label Switching (MPLS) core network. For the label switch router (LSR) to switch Layer 2 virtual circuits (VC), it must have IP connectivity to transport any Layer 2 attachment services. Thus, the edge LSRs must have the capability to switch Layer 2 VCs.

The EoMPLS can configured as below.

•  Router to RouterPort Based
•  Router to RouterVLAN Based
•  VLAN Rewrite
•  Switch to SwitchVLAN Based
•  Switch to SwitchPort Based
• VLAN Rewrite in Cisco 12000 Series Routers

 The Below link show how to configure Router to Router VLAN Based EoMPLS.

VLAN Based EoMPLS

Importing Routes from Global Table into a VRF Table

Every time I saw that we leake route from VRF to global routing table, So VRF can use the Global routing table for Internet Accsess ( Internet over L3 VPN ) or for specific network access.

But heere we are going to see that If we want to import routes from Global routing table to VRF then how  we can configure the network device .

Using the feature know as Import Route Map  ( import ipv4 unicase | multicast )

The BGP Support to Import routes  from Global Table into a VRF Table feature introduces the capability to import IPv4 unicast prefixes from the global routing table into a Virtual Private Network (VPN) routing/forwarding instance (VRF) table using an import route map.

Below is the Example :

ip prefix-list chetan seq 10 permit x.x.x.x/x


ip prefix-list chetan seq 20 permit x.x.x.x/x
ip prefix-list chetane seq 30 permit x.x.x.x/x
!

ip vrf ckumar
rd 50:1

import ipv4 unicast map CHETAN_IMPORT
route-target export 50:1

route-target import 50:1

!

exit

!

route-map CHETAN_IMPORT permit 10

match ip address prefix-list chetan

Cisco IOS Release Naming

Letter Definitions for Cisco IOS Release Trains

The first character assigned to the release is based on the technology specific to that release. These are technology characters utilized in Cisco's IOS Release deployment.


A = Aggregation/Access Server/Dial technology


B = Broadband

C = Core routers (11.1CA, 11.1CT, 11.1CC)

D = xDSL technology

E = Enterprise feature set

F = Feature Specific enhancements (11.2F)

G = Gigabit Switch Routers (GSR)

H = SDH/SONET technology (11.3HA)

J = Wireless Networking technology (Aironet)

M = Mobile (Restricted to Mobile Wireless BU usage and further reserved for Mainline)

N = Voice, Multimedia, Conference (11.3NA)

P = Platform features (11.2P)

R = Reserved for ROMMON reference

S = Service Provider

T = Reserved for Consolidated Technology Train

W = LAN Switching/Layer 2 routing

X = A short lived, one-time release (12.0XA)

Y = A short-lived, one-time release (when Xs are exhausted)

Z = A short-lived, one-time release (reserved if Ys are exhausted

Cisco IOS S Family Numbering