Cisco Study Blog

Virtual Router and Forwarding aka VRF’s

VRF is an independent router: Interface and IP subnets Routing Protocols Routing and Forwarding table VRF’s have one single management option. VRF’s do not have separate management instances unlike ASA’s or Nexus 7K’s   VRF Lite – Cisco terminology of VRF’s without MPLS. VRF Lite can be used to segment a single Physical infrastructure into […]

MPLS Basics


MPLS uses two types of routers LER – Label edge Router LSR – Label Switch router In a VPN environment, the LER is called the Label Edge Router also known as a Provider Edge Router or PE. The Label Switch Router relays MPLS in & out. In a VPN environment the LSR is called the […]

Cisco VPN 642-648 Training Notes

VPN Policy Flow

IPsec remote access (IKEv1) Easy VPN Remote Client & Server (IKEv1) Easy VPN Remote hardware client¬†(ASA 5505 only) Client less SSL remote access AnyConnect SSL remote access (SSL/TLS and Datagram Transport Layer Security [DTLS]) IPsec site to site (IKEv1 and IKEv2) ASA 8.4 allows for LAN-to-LAN [L2L] tunnels bot IKEv1 and IKEv2.) If a Site-to-Site […]

Border Gateway Protocol


What is BGP?     Autonomous Systems Numbers (AS) are owned by business entities and used to advertise public address space to multiple AS’s to allow service to be accessed from the internet. BGP’s default metrics are: AS-path attribute Autonomous system hops. BGP routes (routing table) could contain up to 300,000 routes. BGP routers shoo;d […]

CCNP Questions & Answers


  CCNP¬†Questions & Answers Quick Notes – LAN What is carrier sense multiple access collision detect (CSMA/CD)? CSMA/CD describes the Ethernet access method. In CSMA/CD, many stations can transmit on the same cable, and no station has priority over any other. Before a station transmits, it listens on the wire to make sure no other […]