Certified Network Associate

The key sequence Ctrl + ^ will cancel the copy from flash memory.

Each exclamation point (!) means that one UDP segment has successfully transferred. Each V means that there has been a successful check run verification on a segment.

When you enter the keywords "setup" at the router# prompt, you will enter setup mode. Also a corrupt or new software installation will automatically default to the router setup program.

The Cisco Discovery Protocol (CDP) operates at the datalink layer of the OSI reference model. CDP is used by Cisco internetworking devices to advertise its location and existence in the network.

SNAP (Subnetwork Access Protocol) works on the physical, the other protocols work on high layers.

CDP only works on directly connected routers so you would have to use a higherlayer-protocol tool, such as telnet, to connect to the remote device.

Type "no cdp run" at the Router(config)# prompt Type "no cdp enable" at the Router(config-if)# prompt to disable CDP on an interface. By default, CDP is automatically enable on a router and its interfaces.

The default for the CDP timer is 60 seconds. To configure quicker updates, set the CDP holdtime to less than the CDP timer did.

Router updates will be quicker but bandwidth usage will increase.

The Cisco IOS global configuration command "cdp timer 'seconds' " will specify how often the router will send CDP (Cisco Discovery Protocol) updates.

The Cisco IOS privileged EXEC command "show cdp neighbors" will display information about neighboring routers connected on your network.

The correct syntax is IP host name [ TCP-port-number ] address [ address ]..... So, "IP host P1R1 1.0.0.5 2.0.0.8" is the correct choice. "IP host P1R1 1.0.0.5" only points the host name P1R1 to one IP address--1.0.0.5.

You can only specify six name servers in one command. The syntax is "IP name-server server-address1 [[ server-address2 ]...server-address6]. You must also enable DNS.

The possible responses from the ping command are: ! Successful receipt of an echo reply. . Timed out waiting for a reply U Destination unreachable C Congestion-experienced packet I Ping interrupted ? Packet type unknown & Packet TTL exceeded.

The quality of information is rated: Connected interface 0 Static route 1 IGRP 100 RIP 120 Unknown 255 The lower the value, the more reliable the source with 255 signifying information that the router will ignore. So, the router will use IGRP, rated at 100, before RIP, rated at 120.

"show IP protocol" displays routing timers and network information. "show IP route" displays the routing table with information about all known networks and subnetworks.

The Interior Gateway Routing Protocol (IGRP) will broadcast it's entire routing table to all directly connected neighbors every 90 seconds.

High-Level Data Link Control (HDLC) is a datalink layer protocol that specifies a data encapsulation method for serial links.

Cisco routers use access lists to identify packets for priority or custom queueing, restrict or reduce the contents of routing updates, provide IP traffic dynamic access control with enhanced user authentication using the lock-and-key feature, identify packets for encryption, and identify Telnet access allowed to the router virtual terminals. The Access list enable you to identify packets for priority or customer queuing, restrict or reduce the contents of routing updates, provide IP traffic dynamic access control with enhanced user authentication using the lock-and-key feature. Identify packets for encryption, and Identify Telnet access allowed to the outer virtual terminals.

The access lists are standard and extended. Standard access lists for IP check the source address of packets that could be routed. Extended access lists can check the source and destination packet plus check for specific protocols, port numbers, etc.

DDR is dial-on-demand routing. It provides routing for low volume and periodic traffic. It initiates a call to a remote site when there is traffic to transmit.

The Cisco HDLC frame format is Flag, Address, Control Proprietary, Data, FCS, Flag. The PPP frame format is Flag, Address, Control, Protocol, LCP (Code, Identifier, Length, Data), FCS, Flag. The SDLC and LAPB format is Flag, Address, Control, Data, FCS, Flag.

The first thing checked is to see if the packet is routable or bridgeable. If it is not, the packet will be dropped.

Only traffic from the source network 172.16.0.0 will be forwarded. Non-172.16.0.0 network traffic is blocked. The wildcard mask 0.0.255.255 tells the router to check the first 2 octets and to ignore the last 2 octets.

Only 2 access lists is allowed per interface. One inbound, one outbound. An access list must have conditions that test true for all packets that use the access list.

Put standard access lists as near the destination as possible. Put extended access lists as close to the source as possible. Standard access lists don't specify the destination address.

AppleTalk access lists use numbers in the 600 - 699 range. IP uses 1 - 99 for standard access lists or 100-199 for extended access lists. IPX uses 800 - 899 or 900 - 999 for extended access lists. IPX SAP filters use 1000 - 1099. IP Standard = 1-99, IP Extended = 100-199, IPX Standard = 800-899, IPX Extended 900-999, IPX SAP filters = 1000-1099, and Apple Talk 600-699.

Echo (ping) is port number 7 and port number 21 is FTP. Port number 20 may also need to be added to negate any FTP traffic.

This will block traffic from subnet 172.16.4.0 and allow all other traffic. The first statement "access-list 1 deny 172.16.4.0 0.0.0.255" will deny access to the subnet 172.16.4.0.

It tells the router to check the corresponding bit value. 0=Check 1=Ignore

Cisco uses any to specify 255.255.255.255. This tells the router to ignore all and permit any address to use an access list test. Cisco uses host to specify 0.0.0.0. This tells the router to check all.

Cisco uses host to specify 0.0.0.0. This tells the router to check all. Cisco uses any to specify 255.255.255.255. This tells the router to ignore all and permit any address to use an access list test.

The FastHub 100 Series are nonmanageable and standalone. The FastHub 300 Series are manageable and stackable.

The Cisco IOS interface configuration command "ip helper-address 'address' " is used to provide a host address to receive forwarded UDP and BOOTP broadcasts. The helper address points to a TFTP server and all incoming TFTP requests at this interface are then forwarded to this address.

Traffic from 172.16.4.13 is blocked and all other traffic is allowed. The 0s in all for octets tell the router to check the complete address and to any access. 0.0.0.0 in "access-list 1 permit 0.0.0.0 255.255.255.255" is a placeholder. 172.16.4.13 is denied by the first statement, all other traffic is permitted by the second statement.

This will block ftp traffic since ftp uses ports 20 and 21. This will deny all FTP traffic, but permit all other ip traffic. Both ports 20 and 21 are well known FTP ports.

You can access three forms of WAN services with Cisco routers. Switched or relayed services include X.25, Frame Relay, and ISDN. An interface front end to IBM enterprise data center computers includes SDLC. And, you can access the services of WAN providers using protocols that connect peer devices such as HDLC and PPP encapsulation. IPX/SPX and NetBEUI are LAN protocols.

This Cisco IOS line configuration command "password 'password' " is used to specify a password for non-privileged access.

To set the password on the privileged mode, enter enable-password san-fran. When you type enable at the Router> prompt, you will be prompted for a password. After successfully entering the password, you will get the Router# prompt for the privileged mode.