Welcome!

Cisco certified network associate

welcome!• Goal – Cisco Certified Network Associate, Cisco Certified Network Professional, and beyond!

• About Me

• Overall view of classes

• Switching Basics (frames, broadcast / collision domains, arp)

• Switching advanced (stp, portfast, root bridge, vtp pruning, trunking, port-channels)

• Routing Basics (static, rip, ospf, eigrp)

• Routing advanced (route redistribution, changing metrics)

• Other awesome topics

• NAT, IPv6, Binary / Hex conversion, subnet maths, summarization

• PPP and Frame Relay

• First interview question

• Next…Topics to cover today

Topics to cover• Hardware (Where (decent places), what (3550, 3560, or 2950), why (emulation?)

• Cables / cabling needs (Auto MDIX – medium dependent interface crossover)

• Boot (ROMMON, flash, ROM, RAM, NVRAM, running-config, startup-config), diagnostics

• Switching Basics

• Models (TCP/IP, versus DoD)

• Frames (hubs, repeaters, flooding, broadcast / collision domains) – examples

• VLANing

• Mac addressing (OUI vey)

• Arp

• CDP

• VTP

• Next…Hardware

Hardware• Where (decent places)

• http://www.certificationkits.com/

• What to buy (3550, 3560, or 2950)

• CCNA – 2 2950, or 3550, 2900 series (RAM!)

• CCNP – Add 2 more 3550 and two more 2900 routers

• TSHOOT Exam Topology

• Why (emulation?)

• GNS3 – Wireshark (http://www.gns3.net/download/)

• Cables / cabling needs (Auto MDIX – medium dependent interface crossover)

• 2960 3560 both have Auto MDIX otherwise crossover cables it is

• http://monoprice.com

• Next…Boot

Boot• 1. Bootstrap program ROMmon runs Power On Self Test (POST)

• 2. Bootstrap checks the Configuration Register in startup config file

• If nothing is there it will load from Flash

• No flash it will try to load from a TFTP server (assuming that you have one set up on the network / program one in, ASA)

• If no TFTP server you would have to manually enter TFTP info from ROMMON (SERVER = <tftp server>, SUBNET MASK=<subnet mask>, etc.)

• 3. IOS found now it is loaded into RAM (Self-decompressing the image: ####...)

• 4. Config file loaded from NVRAM (dir) into RAM if none found Setup dialogue

• Next…Switching

Switching basics• Models (Layers, TCP/IP versus DoD, real world)

• Vlanning (Broadcast, Collision domains)

Models• TCP / IP (A Pizza Sure Tastes Nice During Presentations)

• Application – HTTP, everything

• Presentation – Human to computer (Layer 6)

• Session – Build and tear down of session (Layer 5)

• Transport – TCP/UDP (Layer 4) – a.ka. segment

• Network – IP Address (Layer 3) – a.k.a. packet

• Data Link – MAC (Layer 2) – a.k.a. frame

• Physical (Layer 1)

• DoD

• Application (5 and up)

• Host-To-Host Layer (4)

• Internet Layer (3)

• Network Interface Layer (1 and 2)

• Next…Vlanning

VLANing• Broadcast Domains – Stops at a Router (L3 device edge)

• Collision Domains (hubs, repeaters) – Collision, hardware needs to listen for silence

• Switches eliminate this by moving the collision domain to the specific port

• Next…MAC Addresses

MAC addresses• Mac address – unique identifier on a broadcast domain

• Entire thing 6 bytes (48 bits)

• OUI (first 3 bytes – or 24 bits)

• If someone says, “For ease of use I need to duplicate my mac, can I?” What do you ask them?

• Next…Address Resolution Protocol

Address resolution protocol• Arp requests – Hey who has an ip address of 192.168.0.1?

• Send a broadcast out ff:ff:ff:ff:ff:ff

• No MAC supplied in the arp request

• Arp replies – Hey I have it!

• GNS3 example

• Loop traffic? (https://supportforums.cisco.com/message/3005684#3005684) - self looped port

• do wr, copy runnning-config startup-config, wr mem

• Next…Cisco Discovery Protocol

Cisco discovery protocol• Cisco device sends out a multi-cast to 01:00:0c:cc:cc:cc with its mac address as source

• No two way communication just multicasts

References• http://www.9tut.com/cisco-router-boot-sequence-tutorial

• http://www.petri.co.il/introduction-to-the-osi-model.htm