existRSTP (Rapid Spanning Tree Protocol)Learning which，We will know RSTP different fromPVST (Per Vlan Spanning Tree)One of the places，It isPort Roles difference。As different port states believe everyone is familiar with，But the problem of port role，Many books and tutorial included in the classroom are a passing，In retrospect，Students can not help knowing a lot of questions，Let's take a look at this，Among the Rapid Spanning Tree Protocol，How[……]
The internet
BGP recently doing exercises，Do the following topology when encountered some problems，This topology is
I configured the network segment：
among them
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1 2 3 4 5 6 7 8 9 10 11 12 13 |
R1 R1(config-if)#do sh ip int br Interface IP-Address OK? Method Status Protocol FastEthernet0/0 unassigned YES unset administratively down down Serial1/0 192.168.12.1 YES manual up up Serial1/1 192.168.13.1 YES manual up up Loopback1 1.1.1.1 YES manual up up |
|
1 2 3 4 5 6 7 8 9 |
R2 Interface IP-Address OK? Method Status Protocol FastEthernet0/0 unassigned YES unset administratively down down Serial1/0 192.168.12.2 YES manual up up Serial1/1 192.168.24.2 YES manual up up |
[crayon-68cc4335ee9e0[……]
In the EIGRP routing protocol，It does not seem to be able to issue commands directly to the default route，例如default-information originate
That should be how to do it? Here are two common methods：
one、Write a static default route，Then use the command to redistribute default route into EIGRP filling inside，Such routing entry[……]
In the configuration in OSPF，There are portions of the content certification，OSPF authentication is divided into two，They are
- Based authentication area
- Based authentication link (port)
The same time，Authentication mode can also be divided into two，One is plain text authentication，Another is the MD5 encrypted authentication。
Here we do not discuss OSPF encryption method，It is simply illustrative ofRegional links and similarities and differences between these two types of authentication。[……]
OC standard fiber cable is commonly used in today's networks set of standards，Readily not hurt to look at memory。
Optical Carrier (OC) is determined at a level many SONET fiber optic network of a group of signal bandwidth。It is usually expressed as OC-n，among them，n is a multiplication factor，It indicates basic rate is 51.84 Mbit / s the number of times。Currently defined standards：
OC-1 — 51.8 4on[……]
How do network also has a year，Speaking today, a fewAgreement with "arp" in accordance withSome confused old，So I come here to be a simple distinction。
First, that ARP (address resolution protocol)：
This is not difficult to understand，arp protocol used in the computer artTao own MAC address and IP addressin the case of，It used to get the peer IP address corresponding to theMAC address。of course，cross[……]
Some time ago I wroteA simple example Cisco routers DHCP and DHCP relay configuration，Article uses a command to achieve theDHCP forwarding，But this function is exactly how to achieve it? Now let's learn more about this command。
When the terminal equipment andDHCP serverWhen not on the same broadcast domain，Intermediate devices need to specify an address to be broadcast packet forwarded out，That needs to be sethelper_add[……]
Packet Tracer is an auxiliary company published by Ciscolearning tools，Learning courses for beginners to Cisco network design、Configuration、excludeNetwork failureProviding network simulation environment。Users cansoftwareofGraphical User InterfaceUse drag method to establish directNetwork topology，And provide detailed process data packets traveling in the network，Real-time observation of network operation。You can learn IOS configuration、Failure to exercise[……]
Today came across configurationDHCP relayThe problem，Suddenly I found that I had actually not noticed，Even sometimes do not know how to engage，And later I had to Google it very awkward ......，Now recorded as follows：
I was not on the map topology，Simple words to describe：
R1(f0/1)————-(f0/1)R2(f0/0)——S1——PC0
[……]