Jobs in saudi arabia

Parts Salesman
Parts Storekeeper

1800-3100

Parts Picker
Heavy Driver
Invoice r

1500-2500

Sales Manager
9600-1600

Light Driver
1200-2000

Auto Mechanic
Auto Technician
Auto Electrician
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                                                            Contact : Shafqaatsm@yahoo.com

Jobs in saudi arabia

Posted by TechWorld No comments

Parts Salesman
Parts Storekeeper

1800-3100

Parts Picker
Heavy Driver
Invoice r

1500-2500

Sales Manager
9600-1600

Light Driver
1200-2000

Auto Mechanic
Auto Technician
Auto Electrician
Auto Painter

1000+Flate Rate


                                                            Contact : Shafqaatsm@yahoo.com

How Hyper Terminal connection In window For Router is Created?

HyperTerminal is a terminal emulator program that runs in Windows. What this means is that it offers you a text-based command prompt on a remote device. That device could be either a serial device, like a Cisco router, connected directly to your PC’s serial port OR a network device. 

How Hyper Terminal connection In window For Router is Created?

Posted by TechWorld No comments

HyperTerminal is a terminal emulator program that runs in Windows. What this means is that it offers you a text-based command prompt on a remote device. That device could be either a serial device, like a Cisco router, connected directly to your PC’s serial port OR a network device. 

How Multicast Works?

Multicasting is the sending of a single datagram to multiple hosts on a network or internetwork.

How Multicast Works?

Posted by TechWorld No comments

Multicasting is the sending of a single datagram to multiple hosts on a network or internetwork.

How link state Algorithm Work?

Link state protocols work with the following functionality;

• Each router establishes a relationship and adjacency with each of its neighbors.
• Each router sends a data unit to each neighbor, these are called LSA in OSPF.The LSA lists each of the router’s links, and for each link, it identifies the link, the state of the link, the metric cost of the router’s interface to the link, and any neighbors that might be connected to the link. Each neighbor receiving an advertisement in turn forwards (floods) the advertisement to its own neighbors.
• Each router stores a copy of all the LSAs it has seen in a database. If all works well, the databases in all routers should be identical.
• The completed link state database, is used by the Dijkstra algorithm to compute a graph of the network indicating the shortest path to each router. The information for each best path is then sent to the routing table.

How link state Algorithm Work?

Posted by TechWorld No comments

Link state protocols work with the following functionality;

• Each router establishes a relationship and adjacency with each of its neighbors.
• Each router sends a data unit to each neighbor, these are called LSA in OSPF.The LSA lists each of the router’s links, and for each link, it identifies the link, the state of the link, the metric cost of the router’s interface to the link, and any neighbors that might be connected to the link. Each neighbor receiving an advertisement in turn forwards (floods) the advertisement to its own neighbors.
• Each router stores a copy of all the LSAs it has seen in a database. If all works well, the databases in all routers should be identical.
• The completed link state database, is used by the Dijkstra algorithm to compute a graph of the network indicating the shortest path to each router. The information for each best path is then sent to the routing table.

How to Configure NAT in Cisco IOS?

NAT (Network Address Translation), it in simple terms translates an IP address into another. Network Address Translation is of different types like

Static NAT (One to One)

Dynamic NAT (Many to Many)

Overloading (Many to One)

The main purpose of NAT is to hide the IP address (usually private) of a client in order to reserve the public address space. For example a complete network with 100 hosts can have 100 private IP addresses and still be visible to the outside world (internet) as a single IP address. Other benefits of NAT include security and economical usage of the IP address ranges at hand.

We will focus on Overloading form of NAT. This is called as Port Address Translation (PAT) or even Network Address Port Translation (NAPT). NAT Overloading translates many private IP addresses from a Local Area Network (LAN) onto a single registered legal Public IP address. Here, the source IP and the source port get translated to the Public IP and a different source port.

Typical network configuration would be on an Internet Router which enables all the hosts in the LAN to connect to the Internet using one single Public IP address.

The following procedure will help you to configure NAT Overload or Port Address Translation (PAT) in Cisco IOS:

NAT Inside Interface

Enable an interface on the router with an IP Address and mark it as nat inside interface. This is the interface that connects to your internal private network

WANRouter(config)# int fastethernet0/1

WANRouter(config-if)# ip address 192.168.1.1 255.255.255.0

WANRouter(config-if)# ip nat inside 

Enable NAT Outside Interface

WANRouter(config)# int serial0/0/0

WANRouter(config-if)# ip address 100.100.100.100 255.255.255.0

WANRouter(config-if)# ip nat outside

Configure NAT Pool

This will be a pool of legal Public IPs that is bought by the organisation. This could anything from one to many IP Address

WANRouter(config)# ip nat pool WANPOOL 100.100.100.10 100.100.100.10 netmask 255.255.255.0

This creates pool which has just one IP address. The syntax is

ip nat pool <pool name> startip endip {netmask netmask | prefix prefix-length}

Access List to Allow List of IP Addresses to NAT Translate

WANRouter(config)# ip access-list 10 permit 192.168.1.0 0.0.0.255

For more networks or hosts to overload the NAT pool simply add them to the access list

WANRouter(config)# ip access-list 10 permit 192.168.2.0 0.0.0.255
WANRouter(config)# ip access-list 10 permit 192.168.3.0 0.0.0.255

Instruct Router to NAT the Access list to the NATPool

WANRouter(config)# ip nat inside source list 10 pool WANPOOL overload

If this is an internet configuration then ensure that a default route on the IP to the outside IP address or outside interface

WANRouter(config)# ip route 0.0.0.0. 0.0.0.0 serial0/0/0

or

WANRouter(config)# ip route 0.0.0.0 0.0.0.0 100.100.100.100

Thats it. Job done!!!

The NAT setup is now complete.We have setup the router to translate LAN private IPs into the Internet public IPs.

To check the NAT status and statistics

WANRouter# show ip nat statistics

To see the active translations

WANRouter# show ip nat translations

We discussed NAT Overloading above: Cisco IOS NAT configuration. Here, we will configure a Static NAT on Cisco IOS Routers. Static NAT is rather straight forward as it is a one to one NATing between IP addresses as against the NAT Overloading or the Dynamic NAT where the IP addresses from the inside are NATed to a pool of IPs.

NAT Inside Interface

Enable an interface on the router with an IP Address and mark it as Nat inside interface. This is the interface that connects to your internal private network

WANRouter(config)# int fastethernet0/1

WANRouter(config-if)# ip address 192.168.1.1 255.255.255.0

WANRouter(config-if)# ip nat inside

Enable NAT Outside Interface

WANRouter(config)# int serial0/0/0

WANRouter(config-if)# ip address 100.100.100.100 255.255.255.0

WANRouter(config-if)# ip nat outside

Instruct Router to NAT the Source IP Address to that of a NATed IP.

WANRouter(config)# ip nat inside source static 10.1.1.11 172.1.1.11

WANRouter(config)# ip nat inside source static 10.1.1.12 172.1.1.12

WANRouter(config)# ip nat inside source static 10.1.1.13 172.1.1.13

Where 10.1.1.x IPs are NATed to 172.1.1.x

The syntax is

ip nat inside source static x.x.x.x y.y.y.y

That sets up the Static NATs. These can co-exist along with NAT Overloading or Dynamic NATs.

To Check the NAT Status and Statistics

WANRouter# show ip nat statistics

How to Configure NAT in Cisco IOS?

Posted by TechWorld No comments

NAT (Network Address Translation), it in simple terms translates an IP address into another. Network Address Translation is of different types like

Static NAT (One to One)

Dynamic NAT (Many to Many)

Overloading (Many to One)

The main purpose of NAT is to hide the IP address (usually private) of a client in order to reserve the public address space. For example a complete network with 100 hosts can have 100 private IP addresses and still be visible to the outside world (internet) as a single IP address. Other benefits of NAT include security and economical usage of the IP address ranges at hand.

We will focus on Overloading form of NAT. This is called as Port Address Translation (PAT) or even Network Address Port Translation (NAPT). NAT Overloading translates many private IP addresses from a Local Area Network (LAN) onto a single registered legal Public IP address. Here, the source IP and the source port get translated to the Public IP and a different source port.

Typical network configuration would be on an Internet Router which enables all the hosts in the LAN to connect to the Internet using one single Public IP address.

The following procedure will help you to configure NAT Overload or Port Address Translation (PAT) in Cisco IOS:

NAT Inside Interface

Enable an interface on the router with an IP Address and mark it as nat inside interface. This is the interface that connects to your internal private network

WANRouter(config)# int fastethernet0/1

WANRouter(config-if)# ip address 192.168.1.1 255.255.255.0

WANRouter(config-if)# ip nat inside 

Enable NAT Outside Interface

WANRouter(config)# int serial0/0/0

WANRouter(config-if)# ip address 100.100.100.100 255.255.255.0

WANRouter(config-if)# ip nat outside

Configure NAT Pool

This will be a pool of legal Public IPs that is bought by the organisation. This could anything from one to many IP Address

WANRouter(config)# ip nat pool WANPOOL 100.100.100.10 100.100.100.10 netmask 255.255.255.0

This creates pool which has just one IP address. The syntax is

ip nat pool <pool name> startip endip {netmask netmask | prefix prefix-length}

Access List to Allow List of IP Addresses to NAT Translate

WANRouter(config)# ip access-list 10 permit 192.168.1.0 0.0.0.255

For more networks or hosts to overload the NAT pool simply add them to the access list

WANRouter(config)# ip access-list 10 permit 192.168.2.0 0.0.0.255
WANRouter(config)# ip access-list 10 permit 192.168.3.0 0.0.0.255

Instruct Router to NAT the Access list to the NATPool

WANRouter(config)# ip nat inside source list 10 pool WANPOOL overload

If this is an internet configuration then ensure that a default route on the IP to the outside IP address or outside interface

WANRouter(config)# ip route 0.0.0.0. 0.0.0.0 serial0/0/0

or

WANRouter(config)# ip route 0.0.0.0 0.0.0.0 100.100.100.100

Thats it. Job done!!!

The NAT setup is now complete.We have setup the router to translate LAN private IPs into the Internet public IPs.

To check the NAT status and statistics

WANRouter# show ip nat statistics

To see the active translations

WANRouter# show ip nat translations

We discussed NAT Overloading above: Cisco IOS NAT configuration. Here, we will configure a Static NAT on Cisco IOS Routers. Static NAT is rather straight forward as it is a one to one NATing between IP addresses as against the NAT Overloading or the Dynamic NAT where the IP addresses from the inside are NATed to a pool of IPs.

NAT Inside Interface

Enable an interface on the router with an IP Address and mark it as Nat inside interface. This is the interface that connects to your internal private network

WANRouter(config)# int fastethernet0/1

WANRouter(config-if)# ip address 192.168.1.1 255.255.255.0

WANRouter(config-if)# ip nat inside

Enable NAT Outside Interface

WANRouter(config)# int serial0/0/0

WANRouter(config-if)# ip address 100.100.100.100 255.255.255.0

WANRouter(config-if)# ip nat outside

Instruct Router to NAT the Source IP Address to that of a NATed IP.

WANRouter(config)# ip nat inside source static 10.1.1.11 172.1.1.11

WANRouter(config)# ip nat inside source static 10.1.1.12 172.1.1.12

WANRouter(config)# ip nat inside source static 10.1.1.13 172.1.1.13

Where 10.1.1.x IPs are NATed to 172.1.1.x

The syntax is

ip nat inside source static x.x.x.x y.y.y.y

That sets up the Static NATs. These can co-exist along with NAT Overloading or Dynamic NATs.

To Check the NAT Status and Statistics

WANRouter# show ip nat statistics

10 Things to Know About the Cisco CCNA Voice Certification

The new Cisco CCNA Voice certification can help you verify that you have the specialized voice- over-IP (VoIP) skills that are in high demand among employers. Not sure if the Cisco CCNA Voice certification is the right path for your career? Read on for information and resource links that will help in your decision making.

1. What are the industry trends that motivated Cisco to create the CCNA Voice concentration?

Today, organizations of all types are moving toward a single, IP-based network that carries data, voice, and video traffic. But VoIP and related applications have characteristics and issues that are distinctly different from those of data traffic. Understanding voice networking requires specialized knowledge and skills, a fact that many employers now recognize.

Another important consideration is to meet the transition needs of organizations that currently operate traditional telecom environments. The move from analog TDM to digital VoIP technology systems continues to drive infrastructure improvements for organizations of all sizes and industries. Up to 80 percent of global companies are evaluating IP telephony solutions. These companies are seeking the productivity, cost, and end-user feature benefits that come with using the network as the platform for VoIP.

2. What do employers say about their needs for people with this type of knowledge and skill?

According to a Forrester Consulting Research: Closing the IT Skills Networking Gap on behalf of Cisco, 69 percent of approximately 1500 companies surveyed expect to employ a dedicated voice specialist by 2012. Only 40 percent of respondents have voice specialists today, which translates to a nearly 75 percent growth rate for these jobs.

3. Where will the CCNA Voice concentration be the most relevant?

With the Cisco CCNA Voice certification, you’ll be ready for specialized job roles such as voice administrator, voice engineer, and voice manager. The CCNA Voice training and certification are for people early in their VoIP careers, as well as for career IT professionals who wish to gain VoIP expertise and skills.

The CCNA Voice certification will give you an overview of Cisco Unified Communications applications (presence, mobility, video, TelePresence, and so on). You’ll learn the skills to handle voice infrastructure (IP telephony hardware, handsets, call manager software, voicemail, and so on). In contrast to vendor-neutral certifications, passing the CCNA Voice exam confirms that you can perform baseline installation, operation, and maintenance tasks on Cisco VoIP solutions, particularly for the Smart Business Communications System telephony system for 8 to 250 phone lines.

4. Is the CCNA Voice path right for you?

The choice to pursue a networking specialist or generalist path is an important career decision. Your interests, the jobs available in your area, and other factors will likely influence your choice.

Your potential salary is another important factor, and industry surveys show that IT specialists receive higher compensation. Certification Magazine’s 2007 annual salary survey found a worldwide average salary of US$74,810 for people with a CCNA certification. In comparison, attaining the professional-level Cisco CCVP certification beyond the CCNA resulted in a 23 percent higher salary, at an average of US$92,350.

All of the CCNA concentrations help you to distinguish yourself in the highly competitive world of IT networking. CCNA Voice takes full advantage of your current CCNA certification as a foundation, while specifically preparing you for new career opportunities in voice networking.

CCNA remains the certification of choice for individuals who want to demonstrate a solid foundation in core routing and switching skills, and then later advance as network generalists.

5. Will the CCNA Voice concentration lead to higher-level certifications?

The CCNA Voice certification is the prerequisite for the CCVP professional-level certification.

6. If I already have a CCNA certification, what’s my best path to becoming a Voice Specialist?

With the introduction of the CCNAs, Cisco has changed the prerequisites and paths to higher-level certifications. To become a voice specialist, one possible path to pursue is shown below. Please note, there are no pre-requisites to become a CCIE.

7. Are there any prerequisites for the CCNA Voice certification?

Passing the original CCNA certification is required before you can receive any of the CCNA concentrations. You may take one or more CCNA certification exams without retaking the original CCNA exam. In addition, through June 23, 2009, CCNA will be accepted as a pre-requisite for CCVP instead of CCNA Voice to accomodate those in process or starting their CCVP.

8. How do you get training for the CCNA Voice certification?

Training for all new CCNA concentrations is available through Cisco Learning Partners and Cisco Learning Solutions Partners

As of mid-2008, instructor-led training courses are only available through Cisco Learning Partners. For CCNA Voice, the recommended training is Implementing Cisco IOS Unified Communications (IIUC), a five-day, instructor-led course.

Cisco Press will offer products for each CCNA concentration. In addition to their best-selling exam certification guides, Cisco Press will offer digital quick reference guides and other online materials to help you prepare for the CCNA Voice exam. Read a sample chapter in the CCNA Voice area

9. What are the details about the CCNA Voice course and exam?

Only one exam is required for the CCNA Voice certification: Cisco 640-460. The suggested IIUC training course covers the components of the Cisco Unified Communications Architecture, public switched telephone network(PSTN) technologies, interconnecting VoIP with service provider networks, Cisco Unified Communications Manager Express, Cisco Unity Express, Cisco Smart Business Communications System Unified Communications 500 Series solution, and basic maintenance and operations tasks for Cisco Unified Communications Manager Express deployments. In-classroom labs enhance the learning experience

10. Where can I get more information about the CCNA Voice concentration?

Visit our CCNA Voice page here on the Cisco Learning Network.

10 Things to Know About the Cisco CCNA Voice Certification

Posted by TechWorld No comments

The new Cisco CCNA Voice certification can help you verify that you have the specialized voice- over-IP (VoIP) skills that are in high demand among employers. Not sure if the Cisco CCNA Voice certification is the right path for your career? Read on for information and resource links that will help in your decision making.

1. What are the industry trends that motivated Cisco to create the CCNA Voice concentration?

Today, organizations of all types are moving toward a single, IP-based network that carries data, voice, and video traffic. But VoIP and related applications have characteristics and issues that are distinctly different from those of data traffic. Understanding voice networking requires specialized knowledge and skills, a fact that many employers now recognize.

Another important consideration is to meet the transition needs of organizations that currently operate traditional telecom environments. The move from analog TDM to digital VoIP technology systems continues to drive infrastructure improvements for organizations of all sizes and industries. Up to 80 percent of global companies are evaluating IP telephony solutions. These companies are seeking the productivity, cost, and end-user feature benefits that come with using the network as the platform for VoIP.

2. What do employers say about their needs for people with this type of knowledge and skill?

According to a Forrester Consulting Research: Closing the IT Skills Networking Gap on behalf of Cisco, 69 percent of approximately 1500 companies surveyed expect to employ a dedicated voice specialist by 2012. Only 40 percent of respondents have voice specialists today, which translates to a nearly 75 percent growth rate for these jobs.

3. Where will the CCNA Voice concentration be the most relevant?

With the Cisco CCNA Voice certification, you’ll be ready for specialized job roles such as voice administrator, voice engineer, and voice manager. The CCNA Voice training and certification are for people early in their VoIP careers, as well as for career IT professionals who wish to gain VoIP expertise and skills.

The CCNA Voice certification will give you an overview of Cisco Unified Communications applications (presence, mobility, video, TelePresence, and so on). You’ll learn the skills to handle voice infrastructure (IP telephony hardware, handsets, call manager software, voicemail, and so on). In contrast to vendor-neutral certifications, passing the CCNA Voice exam confirms that you can perform baseline installation, operation, and maintenance tasks on Cisco VoIP solutions, particularly for the Smart Business Communications System telephony system for 8 to 250 phone lines.

4. Is the CCNA Voice path right for you?

The choice to pursue a networking specialist or generalist path is an important career decision. Your interests, the jobs available in your area, and other factors will likely influence your choice.

Your potential salary is another important factor, and industry surveys show that IT specialists receive higher compensation. Certification Magazine’s 2007 annual salary survey found a worldwide average salary of US$74,810 for people with a CCNA certification. In comparison, attaining the professional-level Cisco CCVP certification beyond the CCNA resulted in a 23 percent higher salary, at an average of US$92,350.

All of the CCNA concentrations help you to distinguish yourself in the highly competitive world of IT networking. CCNA Voice takes full advantage of your current CCNA certification as a foundation, while specifically preparing you for new career opportunities in voice networking.

CCNA remains the certification of choice for individuals who want to demonstrate a solid foundation in core routing and switching skills, and then later advance as network generalists.

5. Will the CCNA Voice concentration lead to higher-level certifications?

The CCNA Voice certification is the prerequisite for the CCVP professional-level certification.

6. If I already have a CCNA certification, what’s my best path to becoming a Voice Specialist?

With the introduction of the CCNAs, Cisco has changed the prerequisites and paths to higher-level certifications. To become a voice specialist, one possible path to pursue is shown below. Please note, there are no pre-requisites to become a CCIE.

7. Are there any prerequisites for the CCNA Voice certification?

Passing the original CCNA certification is required before you can receive any of the CCNA concentrations. You may take one or more CCNA certification exams without retaking the original CCNA exam. In addition, through June 23, 2009, CCNA will be accepted as a pre-requisite for CCVP instead of CCNA Voice to accomodate those in process or starting their CCVP.

8. How do you get training for the CCNA Voice certification?

Training for all new CCNA concentrations is available through Cisco Learning Partners and Cisco Learning Solutions Partners

As of mid-2008, instructor-led training courses are only available through Cisco Learning Partners. For CCNA Voice, the recommended training is Implementing Cisco IOS Unified Communications (IIUC), a five-day, instructor-led course.

Cisco Press will offer products for each CCNA concentration. In addition to their best-selling exam certification guides, Cisco Press will offer digital quick reference guides and other online materials to help you prepare for the CCNA Voice exam. Read a sample chapter in the CCNA Voice area

9. What are the details about the CCNA Voice course and exam?

Only one exam is required for the CCNA Voice certification: Cisco 640-460. The suggested IIUC training course covers the components of the Cisco Unified Communications Architecture, public switched telephone network(PSTN) technologies, interconnecting VoIP with service provider networks, Cisco Unified Communications Manager Express, Cisco Unity Express, Cisco Smart Business Communications System Unified Communications 500 Series solution, and basic maintenance and operations tasks for Cisco Unified Communications Manager Express deployments. In-classroom labs enhance the learning experience

10. Where can I get more information about the CCNA Voice concentration?

Visit our CCNA Voice page here on the Cisco Learning Network.

VLAN Trunking Protocol (VTP) & VTP Modes

What is a VLAN Trunking Protocol (VTP)?

“VTP allows a network manager to configure a switch so that it will propagate VLAN configurations to other switches in the network”

VLAN Trunking Protocol (VTP) is a Cisco proprietary Layer 2 messaging protocol that manages the addition, deletion, and renaming of VLANs for the Cisco Catalyst Switches in the same VLAN Trunking Protocol (VTP) domain. VLAN Trunking Protocol (VTP) enables Cisco Catalyst Switches to exchange and maintain consistent VLAN information amongst a group of Cisco Catalyst Switches.

For example, information for the VLAN 50 defined in Cisco Catalyst Switch A is propagated via VTP updates to all other Cisco Catalyst Switches (Switches B, C and D) in the same VTP domain, the other Cisco Catalyst Switches B, C and D will all end up adding VLAN 50 in their local VLAN data base. VTP is available on most of the Cisco Catalyst Family products.

The comparable IEEE standard in use by other manufacturers is GVRP.

The VTP domain consists of a group of logical group of Cisco Catalyst Switches that are part of the same VTP management domain. A Cisco Catalyst Switch can belong only to one VTP domain at any time.

The VTP domain is a logical group of switches that will share VLAN information. Each switch can belong only to one VTP domain in addition to sharing the VLAN information with all other Cisco Catalyst Switches in the same VTP domain. Cisco Catalyst Switches in different VTP domains drops any VTP updates received from Cisco Catalyst Switches.

In Cisco Catalyst switches the VTP domain can be added through CLI configuration or else it can be learnt from an adjacent VTP Cisco Catalyst switch. We can see this from the example as follows

Switch C is added to the network connecting via a trunk port to Switch B with no VTP domain configured, in this mode when the Switch C receives the first VTP update from the adjacent Switch B, it will become the part of the VTP domain ITKE as identified in the VTP update.

What do you think what happens? If a new Cisco Catalyst switch is placed between any two VTP domains, the Cisco Catalyst switch will join the VTP domain identified by the first VTP update it receives. Just check the following example.

Important Notes about VTP & VTP Modes

Whenever a change occurs in the VLAN database, the VTP server increments its configuration revision number and then advertises the new revision throughout the VTP domain via VTP advertisements.

There three type of VTP modes

VTP Server: The default mode. When you make a change to the VLAN configuration on a VTP server, the change is propagated to all switches in the VTP domain. VTP messages are transmitted out of all the trunk connections. In Server mode we can create, modify, and delete VLANs.

VTP Client: cannot make changes to the VLAN configuration when in this mode; however, a VTP client can send any VLANs currently listed in its database to other VTP switches. VTP client also forwards VTP advertisements (but cannot create VTP advertisements).

VTP Transparent: When you make a change to the VLAN configuration in this mode, the change affects only the local switch and does not propagate to other switches in the VTP domain. VTP transparent mode does forward VTP advertisements that it receives within the domain.

More Related Cisco & Networking Tips:

How to Troubleshoot OSPF?

VLAN Trunking Protocol (VTP) & VTP Modes

Posted by TechWorld No comments

What is a VLAN Trunking Protocol (VTP)?

“VTP allows a network manager to configure a switch so that it will propagate VLAN configurations to other switches in the network”

VLAN Trunking Protocol (VTP) is a Cisco proprietary Layer 2 messaging protocol that manages the addition, deletion, and renaming of VLANs for the Cisco Catalyst Switches in the same VLAN Trunking Protocol (VTP) domain. VLAN Trunking Protocol (VTP) enables Cisco Catalyst Switches to exchange and maintain consistent VLAN information amongst a group of Cisco Catalyst Switches.

For example, information for the VLAN 50 defined in Cisco Catalyst Switch A is propagated via VTP updates to all other Cisco Catalyst Switches (Switches B, C and D) in the same VTP domain, the other Cisco Catalyst Switches B, C and D will all end up adding VLAN 50 in their local VLAN data base. VTP is available on most of the Cisco Catalyst Family products.

The comparable IEEE standard in use by other manufacturers is GVRP.

The VTP domain consists of a group of logical group of Cisco Catalyst Switches that are part of the same VTP management domain. A Cisco Catalyst Switch can belong only to one VTP domain at any time.

The VTP domain is a logical group of switches that will share VLAN information. Each switch can belong only to one VTP domain in addition to sharing the VLAN information with all other Cisco Catalyst Switches in the same VTP domain. Cisco Catalyst Switches in different VTP domains drops any VTP updates received from Cisco Catalyst Switches.

In Cisco Catalyst switches the VTP domain can be added through CLI configuration or else it can be learnt from an adjacent VTP Cisco Catalyst switch. We can see this from the example as follows

Switch C is added to the network connecting via a trunk port to Switch B with no VTP domain configured, in this mode when the Switch C receives the first VTP update from the adjacent Switch B, it will become the part of the VTP domain ITKE as identified in the VTP update.

What do you think what happens? If a new Cisco Catalyst switch is placed between any two VTP domains, the Cisco Catalyst switch will join the VTP domain identified by the first VTP update it receives. Just check the following example.

Important Notes about VTP & VTP Modes

Whenever a change occurs in the VLAN database, the VTP server increments its configuration revision number and then advertises the new revision throughout the VTP domain via VTP advertisements.

There three type of VTP modes

VTP Server: The default mode. When you make a change to the VLAN configuration on a VTP server, the change is propagated to all switches in the VTP domain. VTP messages are transmitted out of all the trunk connections. In Server mode we can create, modify, and delete VLANs.

VTP Client: cannot make changes to the VLAN configuration when in this mode; however, a VTP client can send any VLANs currently listed in its database to other VTP switches. VTP client also forwards VTP advertisements (but cannot create VTP advertisements).

VTP Transparent: When you make a change to the VLAN configuration in this mode, the change affects only the local switch and does not propagate to other switches in the VTP domain. VTP transparent mode does forward VTP advertisements that it receives within the domain.

More Related Cisco & Networking Tips:

How to Troubleshoot OSPF?

How Source Quench Generated?

ICMP - Source quench is generated by a gateway or the destination host and tells the sending end to ease up because it cannot keep up with the speed at which it's receiving the data.

How Source Quench Generated?

Posted by TechWorld No comments

ICMP - Source quench is generated by a gateway or the destination host and tells the sending end to ease up because it cannot keep up with the speed at which it's receiving the data.