Category Archives: Network

Network tools

  Utils SharonTools – Cisco and Juniper Free Labs   Info BGP Potaroo – BGP Global table stats

Ethernet / ARP

Ethernet CSMA/CD Carrier sense multiple access / collision detect  (IEEE 802.3) Ethernet Frame – From 64 to 1518 bytes EtherTypes: 0x0806 – ARP Frame 0x0800 – IPv4 Frame 0x8100 – IEEE 802.1q Frame 0x86DD – IPv6 Frame Jumbo Frames – Ethernet frames with more than 1500 bytes of payload to increase efficiency. Up to 9000… Read More »

Cisco EEM

Embedded Event Manager Last version: Cisco IOS Software is EEM v4.0 Types of EEM policies: Applet policies – using CLI Tcl policies – using Tcl programming language (tool command language) Available on: Switches Ca talyst 3700, 4500, 6500 Routers ISR, 7200, 7300, 7600, 10000, ASR-1000 Components: Event Detectors (or event publisher) Event Manager Server Policy Director… Read More »

Cisco iOS

IOS Images lan lite – Layer 2 entry level switches. 802.1Q, STP, CDP, VTPv2, PAGP/LACP. lan base – [lan lite] + Layer 2 advanced switches. VTPv3. More security and managament functions. ip base – [lan lite] + Very limited routing (static, rip, eigrp stub), ACLs, Private LANs ip voice – [ip base] + VoIP sp services – [ip… Read More »


RIB – BGP Routing Information Base Adj-RIBs-In – Information received from the peers and used for the decision process, before applying any attribute modification or applying route filtering. Local RIB – Information from the result of the processing of the RIBs-In table. After applying decision process and BGP policies. This information will be processed to create the routing… Read More »


LCAP – Link Aggregation Control Protocol – Standard 802.3ad Active / Passive PAgP –  Port Aggregation Protocol – Cisco Propietary Auto / Desirable Mode On – doesn’t define the protocol. Both ports in the etherchannel need to have the same configuration (vlan and trunks). Traffic flow goes through one of the links, it doesn’t use… Read More »


Basic Information Ethernet Frame The type field of the Ethernet frame is: IPv4 – 0x0800 IPv6 – 0x86DD IP Frame The source and the destination address use 128 bits The Next Header field indicates the type of field is next after the IPv6 header: tcp header, routing header, authentication header,… IP Address format 0000.0000.0000.0000.0000.0000.0000.0000 0db8… Read More »


BGP get vr trust protocol bgp rib neighbor IP advertised   VPN Provides information about the VPN get ike cookies get sa active get sa | include [peer ip] get sa id 0x[id 000000XX] Clears the ike or sa session clear ike-cookie [gateway] clear sa [id]   Debugging Commands: Traffic Filters