Administrative Distance

Feb 13, 2009

Advertised Distance is the distance a neighbor router says, or advertises, is the distance to a destination. This is key in electing a feasible successor or backup route. The lower the distance, the better. The lower the value the better the route is believable. These values can be changed with the distance command.

Administrative Distances

Protocol Distance Value

Connected Interface 0
Static routes 1
EIGRP Summary routes 5
EBGP 20
Internal EIGRP 90
IGRP 100


OSPF 110
RIP 120
EGP 140
External EIGRP 170
Internal BGP 200

READ MORE - Administrative Distance

Today Available Web browser List

A Web browser is a software application which enables a user to display and interact with text, images, videos, music, games and other information typically located on a Web page at a Web site on the World Wide Web or a local area network.
  • Internet Explorer
  • Mozilla Firefox
  • Safari
  • Opera
  • Avant Browser
  • Konqueror
  • Lynx
  • Google Chrome
  • Maxthon
  • Flock
  • Arachne
  • Epiphany
  • K-Meleon
  • AOL Explorer.
READ MORE - Today Available Web browser List

f Cisco Router Series


Cisco 2600 Series Routers
The Cisco 2600 series router, with over 70 network modules and interfaces, offers versatility and expandability ideal for branch office connectivity in a multiservice access router. In addition, Cisco 2600 series routers provide flexible LAN and WAN configurations, multiple security options and a range of high performance processors. By deploying Cisco 2600 series routers, companies can consolidate the functions of multiple separate devices into a single, compact package that can be managed remotely.

Cisco 3600 Series Routers
The Cisco 3600 series router is a family of modular, multi-service routers for medium and large size offices as well as smaller Internet Service Providers. Cisco 3600 routers support over 70 modular interface options in a high performance manageable access platform. The Cisco 3600 series routers provide solutions for data, voice, video, hybrid dial access, Virtual Private Networks (VPNs), and multi-protocol data routing while integrating the functions of several devices into a single manageable solution.

Cisco 3700 Series Routers
The Cisco 3700 series multiservice access router enables dramatically higher levels of application and service integration in enterprise branch offices. With on-board LAN/WAN connectivity, new high-density service modules, and support for multiple Advanced Integration Modules (AIMs), the Cisco 3700 series routers deliver internal inline power for the EtherSwitch ports, thus delivering a compelling single platform Branch Office IP Telephony and Voice Gateway solution which enables flexible, incremental, and scalable migration to a converged branch office network.

Cisco 6400 Series Universal Concentrators
The Cisco 6400 carrier-class broadband concentrator is a high-performance, scalable service gateway that enables the selection and delivery of broadband network services, Virtual Private Networks (VPNs) and voice and entertainment-driven traffic over the full suite of access media. Cisco 6400 series concentrators include Service Selection Gateway (SSG), which allows subscribers to dynamically select on-demand services. As the gateway to next generation services, the SSG enables services such as videoconferencing, streaming video, personalized Internet, business-grade Internet, shopping, and gaming to create new revenue streams and help attract and retain subscribers.

Cisco 7200 Series Routers
The Cisco 7200 series router is ideally suited as WAN edge devices for enterprises and service providers. The modularity of Cisco 7200 series routers makes them ideal for enterprises seeking to build scalable solutions based on differing requirements for density, performance, and availability. In addition, Cisco 7200 series routers include a Multiservice Interchange (MIX)-enabled backplane to enable integration of data, voice, and video functions previously performed by separate devices into a single platform.


READ MORE - f Cisco Router Series

Network cabling requirements for ethernet


  • 10Base2 50-ohm coaxial is also called thinnet which is up to 185 meters and supports 30 hosts per segment. Physical and logical bus is used with AUI connectors.
  • 10Base5 50-ohm coaxial is also called thicknet which is up to 500 meters and supports 208 users per segment. It uses a physical and logical bus with AUI connectors. It is up to 2500 meters with repeaters and supports 1024 users for all segments.
  • 10BaseT EIA/TIA category 3, 4, or 5, using two-pair unshielded twisted-pair (UTP) wiring supports one user per segment; up to 100 meters long.RJ-45 connector is used along with star topology.
  • 100BaseTX EIA/TIA category 5, 6, or 7 UTP two-pair wiring supports one user per segment; up to 100 meters long. It uses an RJ-45 MII connector with a physical star topology and a logical bus.
  • 100BaseFX Uses fiber cabling 62.5/125-micron multimode fiber supports point-to-point topology; up to 400 meters long. It uses an ST or SC connector, which are duplex media-interface connectors.
  • 1000BaseCX Copper shielded twisted-pair that can only run up to 25 meters.
  • 1000BaseT Category 5 is a four-pair UTP wiring that can run up to 100 meters.
  • 1000BaseSX MMF using 62.5 and 50-micron core; uses a 780-nanometer laser and can go up to 260 meters.
  • 1000BaseLX Single-mode fiber that uses a 9-micron core, 1300-nanometer laser and can go from 3 km up to 10 km.
READ MORE - Network cabling requirements for ethernet

Cisco Router Configuration Commands


Set a console password to cisco

Router(config)#line con 0
Router(config-line)#login
Router(config-line)#password cisco

Set a telnet password
Router(config)#line vty 0 4
Router(config-line)#login
Router(config-line)#password cisco

Stop console timing out
Router(config)#line con 0
Router(config-line)#exec-timeout 0 0

Set the enable password to cisco
Router(config)#enable password cisco

Set the enable secret password to ciscorouter.

This password overrides the enable password and is encypted within the config file

Router(config)#enable secret ciscorouter

Enable an interface
Router(config-if)#no shutdown

To disable an interface
Router(config-if)#shutdown

READ MORE - Cisco Router Configuration Commands

Mostly Asked Question In CCNA Exam Part III


The Answers is in Bold Style. Maybe my answer are wrong but i tried my best to give you correct answer. if any one think that the answer which i gave its not correct then please feedback me.

1. Which statement is accurate about the CIR in Frame Relay?

  1. It is important to purchase a CIR that matches the highest bandwidth requirements of the enterprise.
  2. The CIR can be no lower than the port speed of the local loop.
  3. The CIR defines the contracted maximum rate available from the service provider on the Frame Relay circuit.
  4. It is possible to burst over the CIR if bandwidth is available.
Question 2

Question 2

2. Refer to the exhibit. A network support technician has been asked to set an IP address on one of the FastEthernet interfaces on a new router. What is causing the interface to reject the address?

  1. The IP address is already in use.
  2. The technician is using a network address.
  3. The technician is using the wrong subnet mask for /26.
  4. The technician must enable VLSM on the interface.
Question 3

Question 3

3. Refer to the exhibit. Because of continuing instability of one of the serial links in the OSPF network, a network administrator configures router ASBR as shown. Which two statements will be a result of this configuration? (Choose two.)

  • Traffic intended for destinations across unstable serial links will be forwarded by ASBR even when the links are down.
  • A summary route of 192.168.0.0/22 will be advertised to the ISP router.
  • Serial links in range 192.168.0.0 255.255.252.0 will be forced into a passive state.
  • Networks connected to the unstable serial links will be placed in an unreachable state.
  • Negative effects of route flapping will be reduced.
Question 4

Question 4

4. Refer to the exhibit. Which IP addressing scheme would be correct for the network?

  • H1-172.18.0.10/16
    H2-172.18.0.11/16
    H3-172.18.0.12/16
  • H1-172.18.0.10/16
    H2-172.19.0.10/16
    H3-172.18.0.11/16
  • H1-172.18.0.10/16
    H2-172.18.0.11/16
    H3-172.19.0.11/16
  • H1-172.18.0.10/16
    H2-172.19.0.11/16
    H3-172.19.0.11/16
Question 5

Question 5

5. Refer to the exhibit. What two conclusions can be drawn from the displayed output? (Choose two.)

  • A packet with a destination IP address of 172.20.1.14 will exit the router via the Serial 0/1/0 interface.
  • The default administrative distance for EIGRP has been changed.
  • Network 172.20.1.4 can be reached through two possible routes of equal cost
  • The addresses on this network were created using VLSM.
  • The router connected to Serial 0/1/1 is advertising four separate routes through EIGRP to this router.

I will post more questions soon please comment on it and for any other queries asif (dot) javed (at) yahoo (dot) com

READ MORE - Mostly Asked Question In CCNA Exam Part III

Mostly Asked Question In CCNA Exam Part I


Here i am going to post some mostly asked question in CCNA exam the Bold text is the answer. maybe my answer are wrong but i tried my best to give you correct answer. if any one think that the answer which i gave its not correct then please feedback me.

1. What are three advantages of NAT implementations? (Choose three.)

  1. improved security
  2. improved router performance
  3. decreased processor load
  4. improved scalability
  5. universal application compatibility
  6. sharing few public IP addresses with many hosts

2. In an 8 bit binary number, what is the total number of combinations of the eight bits?

  1. 128
  2. 254
  3. 255
  4. 256
  5. 512
  6. 1024

3. Which option shows the proper notation for an IPv6 address?

  1. 2001,0db8,3c55,0015,abcd,ff13
  2. 2001-0db8-3c55-0015-abcd-ff13
  3. 2001.0db8.3c55.0015.abcd.ff13
  4. 2001:0db8:3c55:0015::abcd:ff13

4. What are two reasons that NAT was developed? (Choose two.)

  1. to preserve registered public IP addresses
  2. to allow users on the public Internet to access local networks
  3. to provide a method for privately addressed LANs to participate in the Internet
  4. to make routing protocols operate more efficiently
  5. to allow private addresses to be routed on the public Internet
  6. to reduce overhead and CPU usage on gateway routers

5. Which IPv4 class of addresses provides the most networks?

  1. Class A
  2. Class B
  3. Class C
  4. Class D
  5. Class E

6. Which statement describes NAT overload or PAT?

  1. Each internal address is dynamically translated to an individual external IP address.
  2. A single internal address is always translated to the same unique external IP address.
  3. Many internal addresses can be translated to a single IP address using different port assignments.
  4. Many internal addresses are statically assigned a single IP address and port to use for communications.

7. Which two statements describe classful IP addresses? (Choose two.)

  1. It is possible to determine which class an address belongs to by reading the first bit.
  2. The number of bits used to identify the hosts is fixed by the class of the network.
  3. Only Class A addresses can be represented by high-order bits 100.
  4. Up to 24 bits can make up the host portion of a Class C address.
  5. Up to 24 bits can be used to identify unique networks.
  6. Three of the five classes of addresses are reserved for multicasts and experimental use.

8. Which statement accurately describes public IP addresses?

  1. Public addresses cannot be used within a private network.
  2. Public IP addresses must be unique across the entire Internet.
  3. Public addresses can be duplicated only within a local network.
  4. Public IP addresses are only required to be unique within the local network.
  5. Network administrators are free to select any public addresses to use for network devices that access the Internet.

9. Which port numbers are used by PAT to create unique global addresses?

  1. 255 and below
  2. 1024 and below
  3. 1025 and above
  4. 64,000 and above

10. Static NAT works by mapping a specific inside local IP address to what other specific address type?

  1. inside global
  2. outside local
  3. outside global
  4. private IP address

I will post more questoins soon please comment on it and for any other queries asif.javed (at) yahoo (dot) com

READ MORE - Mostly Asked Question In CCNA Exam Part I

Difference between Classful and Classless Routing


Classful

  • Classful routing protocols strictly follow the subnet masks i-e. for Class A (8-bit prefix or /8), B (16-bit prefix or /16), and C (24-bit prefix or /24).
  • Do not carry subnet mask information on their routing updates. This makes them unsuitable for hierarchical addressing that require Variable Length Subnet Mask (VLSM) and discontiguous network.
  • All devices in the network must use the same subnet mask therefore when running a classful routing protocol on a network, make sure you use the same subnet mask everywhere. Otherwise, routing black holes can occur.
  • RIP v1 and IGRP are classful routing protocols.

Classless

  • Classless routing protocols do carry subnet mask information on their routing updates.
  • Allow summarization of routes into smaller, more manageable groups.
  • Classless routing is also known as supernetting or Classless Inter-Domain Routing (CIDR).
  • Classless routing protocols extend the standard Class A, B, or C IP addressing scheme by using a subnet mask or mask length to indicate how routers must interpret an IP network ID.
  • Classless routing protocols include the subnet mask along with the IP address when advertising routing information. Subnet masks representing the network ID are not restricted to those defined by the address classes, but can contain a variable number of high-order bits. Such subnet mask flexibility enables you to group several networks as a single entry in a routing table, significantly reducing routing overhead.
  • Classless routing protocols includes RIP v2 and OSPF, Border Gateway Protocol version 4 (BGP4) and Intermediate System to Intermediate System (IS-IS).
READ MORE - Difference between Classful and Classless Routing

Learn the difference between PIX and ASA


For many years, the Cisco PIX has been the established Cisco firewall. But in May 2005, Cisco introduced a new offering—the Adaptive Security Appliance (ASA). However, the PIX is still available. I’ve often heard people ask about the differences between these two product lines. Let’s take a look.

What is a Cisco PIX?

A Cisco PIX is a dedicated hardware firewall appliance. All Cisco PIX versions have model numbers in the 500s. The most popular model for home offices and small networks is the PIX 501; many midsize companies use the PIX 515 as a corporate firewall.

PIX firewalls run the PIX operating system. While the PIX OS is quite similar to the Cisco IOS, there are enough differences to cause some frustration for users more familiar with IOS.

The firewall sports the PIX Device Manager (PDM) for a graphical interface. This GUI is a Java application downloaded through a Web browser.

Typically, a PIX firewall has an outside interface that connects to the inside of an Internet router and goes to the public Internet. It also has an inside interface that connects to a LAN switch, going to the private internal network.

What is a Cisco ASA?

A Cisco ASA is a new firewall and anti-malware security appliance from Cisco Systems. (Don’t confuse this product with what a PIX uses for stateful packet filtering—the adaptive security algorithm, or ASA.)

ASA models are all in the 5500 series. The Enterprise Editions include four versions: Firewall, IPS, Anti-X, and VPN. There’s also a Business Edition for small to midsize companies.

In total, there are five models of the Cisco ASA. All run the ASA version 7.2.2 software, and the interface is much like the Cisco PIX. Both the Cisco PIX and ASA models vary in performance, but the ASA’s lowest model offers much more performance than the base PIX.

Like the PIX, the ASA can also serve as an intrusion prevention system (IPS) and VPN concentrator. In fact, the ASA could take the place of three separate devices—a Cisco PIX firewall, a Cisco VPN 3000 Series Concentrator, and a Cisco IPS 4000 Series Sensor.

Now that we’ve covered the basics of each security appliance, let’s see how they compare.

While the PIX is an excellent firewall, the landscape of security has changed over the years. It’s no longer sufficient to protect your network with a stateful packet filtering firewall. There are so many new threats to a network—including viruses, worms, unwanted applications (e.g., P2P, games, instant messaging), phishing, and application-layer attacks.

When a device does protect against this variety of threats, we say it offers “anti-X” capability or “multi-threat” protection. But the PIX just hasn’t been able to offer this level of protection.

Most organizations don’t want to have a PIX performing stateful firewall filtering and some other appliance protecting you from other threats. Instead, they want an “all-in-one” device—or a unified threat management (UTM) device.

The ASA does offer protection from these different types of attacks. It can even be more of a UTM device—however, it needs a Content Security and Control Security Service Module (CSC-SSM) to be a real UTM. This is the module in an ASA that performs the anti-X functions. Without the CSC-SSM, the ASA functions more like a PIX.

So which one is right for your organization? As always, the answer lies with your organization’s unique needs. However, I would choose the ASA over the PIX any day. First of all, an ASA typically costs less than a similarly featured PIX. Besides the cost incentive, it just seems like a logical choice to choose the newer and faster technology.

For those who already use the Cisco PIX, Cisco has produced a Migration Guide (PDF) that addresses how to migrate from a Cisco PIX to an ASA. In my opinion, this offering foreshadows Cisco’s impending discontinuation of the PIX. While the company has made no announcements to this effect, I think it’s only a matter of time.

Remember, we can no longer rely solely on a firewall to protect our organizations from the varied threats of the Internet; a multifaceted approach is now necessary for complete protection. While the ASA is a good choice, it isn’t your only option. Many vendors offer products to compare the ASA against before making that choice.

READ MORE - Learn the difference between PIX and ASA

Distance Vector Protocols Vs Link State Protocols


Distance Vector

  • Router will advertise a route as a vector of direction and distance.Direction refers to a port that leads to the next router along the path to the destination, and distance is a metric that indicates the number of hops to the destination
  • Distance Vector protocols determine best path on how far the destination is.
  • Examples of distance-vector routing protocols include RIPv1 and 2 and IGRP.
  • EGP and BGP are not pure distance-vector routing protocols but their concepts are the same. In many cases, EGP and BGP are considered DV (distance-vector) routing protocols.
  • A distance-vector routing protocol requires that a router informs its neighbors of topology changes periodically and, in some cases, when a change is detected in the topology of a network.
  • Distance-vector routing protocols are simple and efficient in small networks, and require little, if any management.

Link-state

  • Examples of link-state routing protocols include OSPF and IS-IS.
  • The basic concept of link-state routing is that every node constructs a map of the connectivity of the network, in the form of a graph showing which nodes are connected to which other nodes.
  • The link-state routing requires each switching node in the network to send its information about its neighbours to the entire internetwork.
  • Each node then independently calculates the best next hop from it for every possible destination in the network. (It does this using only its local copy of the map, and without communicating in any other way with any other node.) The collection of best next hops forms the routing table for the node.
  • This contrasts with distance-vector routing protocols, which work by having each node share its routing table with its neighbors. In a link-state protocol, the only information passed between the nodes is information used to construct the connectivity maps.
READ MORE - Distance Vector Protocols Vs Link State Protocols

Cisco Career Certifications Path


General Certifications: Three Levels of Certification

  • Associate: The first step in Cisco networking begins at the Associate level, which also includes CCENT, an interim step to Associates for those with little job experience. Think of the Associate level as the apprentice or foundation level of networking certification.
  • Professional. This is the advanced or journeyman level of certification.
  • Expert. This is CCIE, the highest level of achievement for network professionals, certifying an individual as an expert or master.

General Certifications: Six Different Paths

  • Routing and Switching: This path is for professionals who install and support Cisco technology-based networks in which LAN and WAN routers and switches reside.
  • Design: This path is aimed at professionals who design Cisco technology-based networks in which LAN and WAN routers and switches reside.
  • Network Security: This path is directed toward network professionals who design and implement Cisco Secure networks.
  • Service Provider: This path is aimed at professionals working with infrastructure or access solutions in a Cisco end-to-end environment primarily within the telecommunications arena.
  • Storage Networking: This path is for professionals who implement storage solutions over extended network infrastructure using multiple transport options.
  • Voice: This path is directed toward network professionals who install and maintain Voice solutions over IP networks.

Certification Paths: Routing & Switching

Associate: CCNA

Professional: CCNP

Expert: CCIE Routing & Switching

Certification Paths: Design

Associate: CCNA & CCDA

Professional: CCDP

Expert: CCDE

Certification Paths: Network Security

Associate: CCNA Security

Professional: CCSP

Expert: CCIE Security

Certification Paths: Service Provider

Associate: CCNA

Professional: CCIP

Expert: CCIE Service Provider

Certification Paths: Storage Networking

Associate: CCNA

Professional: CCNP

Expert: CCIE Storage Networking

Certification Paths: Voice

Associate: CCNA Voice

Professional: CCVP

Expert: CCIE Voice

Certification Paths: Wireless

Associate: CCNA Wireless

Professional: Coming Soon

Expert: CCIE Wireless

READ MORE - Cisco Career Certifications Path

How to run EXEC (Privilege Mode) Commands in Configuration Mode


Exec commands can be issued from within configuration mode via the do command. This can be handy for double-checking the current configuration before applying any changes. You can now issue EXEC-level Cisco IOS commands (such as show, clear, and debug commands) from within global configuration mode or other modes by issuing the do command followed by the EXEC command.

Note:You cannot use the do command to execute the configure terminal EXEC command because issuing the configure terminal command changes the mode to configuration mode.

Command:

Router(config)# do command
Router(config)#

or

Router(config-if)# do command
Router(config-if)#

command—The EXEC command to be executed.

Supported Platforms:

  • Catalyst 5000 family ATM modules
  • Catalyst 6000 family ATM modules
  • Catalyst 6000 family switches
  • Catalyst 8510 switch routers
  • Catalyst 8540 switch routers
  • Cisco ONS 15000 series routers
  • Cisco 7100 series
  • Cisco 7200 series
  • Cisco 7500 series
  • Cisco 7600 Series Internet Router
  • LightStream 1010 switch routers
READ MORE - How to run EXEC (Privilege Mode) Commands in Configuration Mode

Concepts regarding EIGRP Tables


EIGRP Tables

EIGRP keeps three active tables in its database.

Topology Table – Is kept for each protocol. It is a table of all the route entries the router has learned. Syntax: show ip eigrp topology shows the number of successors, active or passive, and distance to destination.

Neighbor Table – EIGRP keeps a table for each adjacent router and one for each protocol.

Syntax: show ip eigrp neighbors

Routing Table – Each protocol has its own routing table. EIGRP calculates the best route, or successor, from the topology table and puts the entry in the routing table.

Syntax: show route eigrp

READ MORE - Concepts regarding EIGRP Tables

Apple teams up with Adobe for iPhone Flash at long last

Once thought to be building Flash for the iPhone mostly on its own, Adobe has mentioned at the World Economic Forum that it’s not only continuing work on the animation plug-in but has teamed up with Apple to make it a reality.

In an interview with Bloomberg at the Davos, Switzerland event, Adobe chief Shantanu Narayen describes development as a complicated two-way process rather than maintaining the previous image of a one-sided effort that would depend on App Store approval before it could launch. “It’s a hard technical challenge, and that’s part of the reason Apple and Adobe are collaborating,” he says. “The ball is in our court. The onus is on us to deliver.”

What hurdles Adobe has to overcome aren’t mentioned by the executive, though the company’s long porting process has underscored the difficulty involved. Narayen had said that he was “pleased with progress” as far back as June of last year — just three months after the iPhone SDK made native third-party apps an option on the touchscreen device.

Source: Apple Insider

READ MORE - Apple teams up with Adobe for iPhone Flash at long last

NASA plans industry day on IT infrastructure strategy

NASA plans to hold an industry day July 23 in Washington to brief the private sector on the acquisition strategy for its Information Technology Infrastructure Improvement program (I3P).

The I3P solicitation will support several agency components and encompass network communications, data center, desktop and Web services, according to an announcement on the Federal Business Opportunities Web site.

In addition to communicating its acquisition strategy, NASA will describe its IT infrastructure requirements across the components, get input from industry on its IT strategy and establish a list of companies interested in the procurement.

Registration, which closes July 21, is limited to two representatives per company, NASA said.

The event will be held at the Ronald Reagan Building and International Trade Center.
By William Welsh
READ MORE - NASA plans industry day on IT infrastructure strategy

SVAT CCDBW Wired Mini Black & White CCD Pinhole Covert Camera Set










SVAT CCDBW Wired Mini Black & White CCD Pinhole Covert Camera Set is CCTV mini camera, This wired camera is very small (31x31x18mm) but just as powerful as most full size cameras with a high resolution of 380 TV lines. The size makes it easy to conceal in objects you already have in your home or office.


This small wired spy camera easily connects to a TV, VCR, computer or DVR for recording giving you the opportunity to see what the Spy Eye sees at any time. Because of its small size, the Spy Eye CCDBW camera can easily and discretely be hidden anywhere.
For more and complete reviews you can go to http://www.covisec.com, or maybe for coplete sriteria you can go here. This little thing can use as your security surveillance camera, because nowadays our home security is need to be more intens care and with this little things you can easily double spy and watch your home security or office from burgler.


ps : image taken from http://www.covisec.com/product/CCDBW?META=bizrate-CCDBW
READ MORE - SVAT CCDBW Wired Mini Black & White CCD Pinhole Covert Camera Set

 
 
 
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