TCP Header 20-bytes without options 😀
UDP Header 8-bytes 😀
Ethernet Header 20 bytes
Frame Relay Header 4-6 bytes
Point-to-Point Header 6 bytes
IP Header 20 bytes
EGP Protocols -like BGP- are used between AS
Neighbor table & Topology table in EIGRP are kept in RAM
Inverse ARP maps DLCI to IP
In MAC address the 1st 3-Bytes (24-bits) are the OUI (Organizationally Unique Identifier)
The Command #show ip ospf interface …. gives you the hello timer
Routing table Samples R=Rip , I=IGRP , D=EIGRP , O=OSPF , C=Connected Directly , S=Static Route
In OSPF, DR collects & distributes the routing updates then sends them through Multicast address 224.0.0.5 to Non-DR routers
Non-DR routers send updates to 224.0.0.6 to the DR
All OSPF routers (DR & Non-DR) send hello using 224.0.0.5
OSPF sends hello every 10 secs and the dead time is 4 x hello = 4 x 1- = 40 secs
EIGRP sends hello every 5 secs (every60 seconds on WAN links) and the dead time is 3 x hello = 3 x 5 = 15 secs
EIGRP uses Multicast address 224.0.0.10 to send updates and hellos
EIGRP use DUAL to determine loopfree paths
EIGRP uses RTP to ensure reliable delivery of updates and uses seq. number to ensure order
EIGRP does not use TCP or UDP, instead it uses RTP
RIP broadcast every 30 secs and uses multicast address 224.0.0.9
IGRP broadcast routing table every 90 secs
TCP Ports Telnet 23, FTP 20, 21 , DNS 53, HTTP 80, HTTPS 443, SMTP 25
UDP Ports DNS 53, SNMP 161, TFTP 69
802.1D STP
802.1W RSTP
802.1Q Trunk
802.1ad LACP
802.1p QoS
That’s enough for now i’ll continue soon, hope to see some comments to encourage me to finish it fast 😀
If there are mistakes or any questions plz say..
~ by Network Techs. on September 1, 2009.
Posted in CCNA, cisco
Nice Tips
waiting 4 more
I am also preparing 4 CCNA Exam next month ISA
Good Luck 🙂
MMF said this on September 2, 2009 at 1:05 AM |
Thank you , I did my CCNA exam last year el 7amdullellah, if you need any help please ask,
i’ll be putting some tips for the exam and a link for w sample from cisco web site that simulates the theme of the exam, it will help you know what is the style of the questions and how to answer them, don’t worry the exam is not that hard just calm down and relax in the test room 😉
networktechs said this on September 2, 2009 at 1:12 AM |
okay 🙂
U have my mail, you can add me and we can have chat 🙂
I love chatting with people sharing the same target or track 🙂
MMF said this on September 2, 2009 at 4:03 PM |
thank alot eng
Hassanlce said this on December 13, 2009 at 11:21 PM |
[…] I just created a new blog and added some notes from the CCNA that will help in revisions before the exam hope they are good CCNA NOTES 1 […]
CCNA small but helpfull notes | IT Certification said this on May 2, 2011 at 4:44 PM |