Showing posts with label TLOC. Show all posts
Showing posts with label TLOC. Show all posts

Wednesday, 28 July 2021

LISP - OMP - BGP EVPN Interoperability - Part III: SD-WAN Control Plane

 Introduction

 

Figure 2-1 shows the Control Plane operation when host EP1 using IP 172.16.100.10/32 joins the network. In the previous chapter, we saw how Edge-xTR-11 learned the IP address and registered it to MapSrv-22 by using the LISP Map-register Message where the Instance-Id 100 represents Virtual Network-Id (VN-Id). MapSrv-22, in turn, advertised the NLRI to Border-PxTR-13 as BGP VPNv4 Update message where extended community RT 1:100 (=VN-Id) is used as a kind of VPN identifier (BGP VPNv4 route import/export policy is based on RT value). This chapter first explains how Border-PxTR-13 sends BGP IPv4 Update message to local SD-WAN device vEdge-1. The eBGP peering between Border-PxTR-13 and vEdge1 is VRF based and BGP updates over it don’t carry any VN-Id. vEdge-1 imports the routing information from BRIB to RIB. Then it advertises the routing information by using OMP (Overlay Management Protocol) to the SD-WAN centralized Control Plane vSmart over the DTLS tunnel using System-IP as an originator-Id and VPN label 1003 as a VN-Id. vSmart forwards this update to SD-WAN device vEdge-2 located in Datacenter. vEdge-2 installs the route into the routing table. After that, it exports the routing information from the RIB to the BGP process and sends the BGP IPv4 Update message to Border-Leaf-13 over VRF NWKT eBGP peering without VN-Id.



Figure 2-1: Overall Control-Plane Operation.

Friday, 9 April 2021

Cisco SD-WAN - Part III: Overlay Management Protocol

 

Introduction

 

This chapter introduces the operation of the Overlay Management Protocol (OMP). It starts by introducing TLOC Routes which are used for establishing tunnels between vEdges. Next, it explains OMP Routes which in turn are used for advertising client VPN-specific networks reachability information. I am also going to show the data plane encapsulation when data is sent between the hosts in site 10 and site 30. The purpose of the data plane section is to show how the label attribute advertised within OMP routing advertisements is used to identify customer VPN. In order to see inside captured packets, I am using GRE tunnels instead of IPSec. Figure 3-1 illustrates the example topology used in this chapter. The customer VPN 10 is used on both sites. Site 10 subnet is 172.16.10.0/24 and site 30 subnet is 172.16.30.0/24. Interface ge0/­0 in both vEdges is connected to the Public-Internet, and interface ge0/1 is the connected to MPLS transport network where the customer has its dedicated MPLS VPN.



Figure 3-1: SD-WAN Example Topology.

Monday, 22 March 2021

Cisco SD-WAN - Part II: Manual vEdge Provision Process

Introduction

 

This chapter explains how we can provision vEdge devices manually. It starts by explaining how to build an initial system and tunnel interface configurations. Then it goes through the various certificate installation steps (CA root certificate, Certificate Signing Request (CSR), and granted certificate). After the initial configuration and certificate process section, this chapter shows how we can verify the Control Plane operation. Figure 2-1 illustrates our example topology. For simplicity, there are only two vEdge devices used in this chapter.


Figure 2-1: SD-WAN Topology.