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Will it be beneficial to study SDN if you are CCNA certified?

CCNA is the leading IT certification course provided by Cisco for those IT experts working in the networking field. Upon completion of this job, the IT professionals can easily demonstrate to their companies that they understand how to strengthen Cisco ideas into the networking field.

To comprehend the SDN, think about just two technical functions in the IT networking field. One is programming, and the other one is dealing with the entire networking gadgets physically. So the SDN relates to the programming skills, which make it possible for any specific to interact with the Cisco devices. It is helpful to study SDN if any individual is in the networking field, regardless of whether he holds any Cisco certification.

SDN represents Software Defined Network, and besides Cisco, many other suppliers have likewise begun releasing this software-based integration to streamline their production efficiency and communicating with them rapidly. This automation is still in progress, which implies understanding SDN can be a plus for any CCNA. It would always be better to get certified in any higher-level IT certification course provided by Cisco.

They can then use these higher-level Cisco IT certs to get promoted to higher-level ranks and earn more money. In brief, many arguments support both two theories of getting licensed with one additional Cisco technical certification to discover SDN.

The reason behind the SDN popularity increase is also because of some restrictions to traditional networking. Traditional networking utilizes a distributed model where procedures like ARP, EIGRP, STP, and so on can be run independently on every network device, making these networking gadgets independent of interacting without any primary device having control over the whole network. Utilizing an SDN controller, the entire network can be managed and monitored according to the vendor’s requirement.

The SDN and CCNA, when combined with the skills of any IT professional working in the networking field, can be helpful to the individual, so it will be a great concept initially to get CCNA certified — going through the SDN and taking the abilities to the next level by getting other Cisco IT accreditations, which unquestionably requires some real difficult work and preparation and correct planning.

The individuals will need to stick with an excellent plan to plan for their whole career lead through all the Cisco IT accreditation courses. Cisco Exam disposes of can be used as an extra supplement in learning and quickly acquiring the abilities while practicing PASSHOT Cisco practice tests. These tests dispose and practice tests can be readily available all over the web.

The Cisco certified trainers are already preparing the PASSHOT Cisco practice tests, and practicing them guarantees to pass any of the Cisco exams in the first attempt.

Therefore, concluding to the end, it is easy to ascertain that the IT experts can enhance their abilities utilizing IT certification courses, which have now ended up being obligatory for these people to showcase their talent by becoming accredited from worldwide reputed technology giants like Cisco, Google, Amazon, RedHat, and so on. Those who choose to become certified get picked by the employers over their non-IT certified peers.

Why SD-WAN is better choice than MPLS in 2021

Thinking about both of the above technologies in mind, we have to through each of them, including their advantages and shortcoming; we can easily choose which of them can be the best choice in 2020. Before taking a glimpse at both of them, SD-WAN is the innovation that has reinvented the IT networking market. SD-WAN has enabled companies to acquire better control over their networking gadgets utilizing a software-defined solution.

Formerly, the standard networks do not enable organizations to have more control over the gadgets since each of the networking devices, including routers and switches, has its own EIGRP, STP, ARP, etc. This indicates that they can be independently communicated; however, utilizing a software-defined technology, they can be more scalable and efficient at the same time.

Cisco SD-WAN solutions provide a cloud-based networking architect that can be handled quickly using Cisco’s vManage software application. This SD-WAN option can be monitored on a real-time basis.

On the other hand, MPLS is a multiprotocol label switching typically used to transfer crucial details over the internet utilizing dedicated links leased by Internet Service Providers (ISPs). When utilizing MPLS, the packets’ story is tagged with their particular labels permits the router to process them without doing thorough package analysis. Multiprotocol label switching circuits are likewise an ubiquitous yet crucial part of lots of services’ IT facilities.

These MPLS have extremely steep bandwidth expenses because they are much pricey than the essential broadband connections and priced per bandwidth basis. The banks mainly use them for their ATM services. MPLS have their advantages and some disadvantages, and cost issues are among the top of such impediments. Numerous companies have accepted using SD-WAN options besides their traditional networking options. This may not be as much affordable for them now. Still, in the future, they can quickly discover SD-WAN options cheaply when they switch utilizing hybrid options, i.e., running both SD-WAN and traditional networks parallel.

In short, the SD-WAN innovation will be a more cost-effective, highly trusted, and scalable technology that will replace the traditional networking options in the future. Cisco and its other rivals have been offering such SD-WAN options to their vendors. However, it is tough to count on other than Cisco as if the service provided by Cisco’s competitor is software-defined or not.

Cisco is the pioneer in the network options market, making it an innovation giant that also provides IT experts certifications for enhancing their skills. These accreditations are challenging since they are developed to examine the person’s technical knowledge thoroughly. Those who want to take these accreditation tests need to prepare before appearing in this exam. The individuals have to prove their abilities in the examination before getting these abilities validated by Cisco.

There are many methods where the individuals can prepare for their upcoming tests, and the resources like Cisco examination discards and the PASSHOT Cisco practice tests can be a simple alternative for supplementing the brain.

They also include related info about the SD-WAN and MPLS and concluding the topic. Both SD-WAN and MPLS have their applications; however, the SD-WAN up until now can be the much better choice to be selected in 2021.PASS HOT

What are the curricula in the brand-new CCNA?

You could use the CCNA syllabus to help the prospects choose whether you want to attempt this certification. The CCNA 200–301 course syllabus would offer you a great idea of what you would need to discover to end up being accredited.

IP Data Networks

The course would include information on how information networks work and how the network’s gadgets would work. It would be covering what TCP/IP models are and how information flows within the information network.

LAN Switching

It would likewise teach you the basics about working with switches work and running switches within a network. It would likewise teach you about verifying your networks using telnet, ping, and SSH and setting up and verifying switch operations.

IP Addressing

Courses covering this part of the syllabus are required to teach you about the requirement for IPv4 and IPv6. They ought to teach you the significant difference between personal and public IP addresses for IPv4. When you would have completed, you are required to describe what proper address plans would be for both IPv4 and IPv6, and you need to be able to discuss the running of IPv4 and IPv6 concurrently. You must also have the ability to define and explain the technologies required to run IPv4 and IPv6 together.

IP Routing

IP routing must be covering the essentials of what a router is in addition to basic routing ideas. It needs to teach you about the process of booting a Cisco router, how to set up a router using the command line process and validating your serial and Ethernet interfaces.

IP Services

A course in IP Services that would be preparing you for the CCNA accreditation test need to teach you what DHCP is and about verifying DHCP on your Cisco router. It needs to explain what ACL is and what would be the functions and applications of type of ACL would be. It needs to also teach and explain to you the critical operation of NAT and the setup of NAT.

Network Security

A course in network security needs to teach you about Network Security. You also need to be proficient in the configuration of other networking gadget security functions.

Troubleshooting

The CCNA accreditation examination might concern various troubleshooting problems, so a CCNA certification course should consist of details about repairing numerous networking problems. It would help if you needed to learn to troubleshoot fundamental router operations. It would help if you discovered how to monitor data and how to make use of NetFlow.

Now that you have obtained the knowledge about what you would have in your CCNA Exam, you must be looking forward to getting in-depth knowledge concerning the same and acquire this certification. If so, you ought to check out the PASSHOT CCNA Braindump to attain success in your first attempt.

Obtain These 4 Core Abilities and Become an IT Pro in 2021

With great deals of prospective locations of development in IT, how would you have the ability to narrow your focus? After looking into completely, the tech recruiters and professionals to share some crucial tech locations, you could consider building the skills as an IT Professionals this year.

1. Agile:

Over the previous year and 2020, we would have been investing significantly in my nimble abilities, as per the founder of Project Management Essentials, Alan Zucker. Scrum Alliance now would be providing Advanced Scrum Master and Scrum Professional accreditations beyond the foundational Scrum Master training.

2. Programming as well as web application advancement:

Some technical abilities spaces would continue to develop opportunities for tech professionals thinking about growing their professions or increasing their marketability. In particular, the two of the hottest requirements for new functions right now are Python and React.

Python (setting language) is considered rather popular right now, mainly for its detailed possible utilization in different software advancement, facilities management, and information analysis workflows, according to the director of recruitment of TalentLab, Sarah Doughty. Reacting would be presented as the most popular JavaScript library for web application development and would likely to be continuing to be an essential sought-after skill throughout 2020.

3. Data analytics:

Understanding your data would be motivating smarter as well as quick service services. My recommendation for specialists who want to stay significant in the IT workforce is to dig into company data analytics. You could begin by trying out or getting trained in using the Data Studio, Microsoft Power BI, or Mixpanel for the product and user behavioral analytics.

4. Open source tools:

Elasticsearch, Logstash, Kibana are thought to be another thing worth looking into if you wish to get the upskilled. ELK is considered to be an intelligent tool for handling your logs. The system would help you gather records from various systems, places, and applications and put them in one place. The plan would allow you to evaluate the logs, develop visualizations for applications, and infrastructure monitoring and security analytics.

Top core abilities: Showcase your EQ.

Complex tech abilities could only take you so far in your career, according to the employers. To play a more integral function in your company, you would likewise have to develop core abilities, which are likewise referred to as soft skills — such as interaction, versatility, and emotional intelligence.

Honing complex abilities, like experience with an in-demand shows language, would have the ability to assist you out in tech specialists advance their professions; however, having a specific technical knowledge is thought about to be no longer sufficient to see your tech profession grow. Business leaders would be providing more weight to soft skills in 2020 than they would be ever had before, based on the words of Doughty.

Now that you have obtained the knowledge about the abilities required to endure in the IT Sector, you should also get the PASSHOT IT Certification Exam Dumps to assist you to attain success in your very first effort.

What are CCNP Data Center jobs in Dubai?

Over the last few years, Cisco accreditations have gotten popular astonishingly. Undoubtedly, Cisco certifications would be deemed the outright most necessary certificates in the field of computer system networking. About Cisco certifications, there would be an extensive range of choices. To help your career and assist you in opening brand-new doors in your career, you need the ideal accreditations.

Cisco introduced its primary certification program in 1998. The essential idea behind the accreditations was to supplement the CCIE or Cisco Certified Internetwork Expert program. Cisco would have extended its qualifications and supplies lots of certifications for experts of all experience levels from that point forward.

CCNP Overview:

CCNP or Cisco Certified Network Professional is considered the certification available for IT specialists with one year of expert experience in computer system networking. A diploma or equivalent in a significant field is also mandatory.

The CCNP accreditation would be created for professionals trying to find particular training programs to preserve, implement, and plan Cisco’s extensive range of high-end network option items. This distinct certification would cover an extensive range, which would spread out the fundamentals of computer system networking. A portion of these would be including:

Cisco advanced routing
Cisco multilayer changing
Cisco remote access
Converged network optimization
Scalable internet works

CCNP Data Center Certification and Training would cover core technologies and an information center that would be a focusing area of your option. You would be selecting where you prefer to focus. You choose where to take your career.

Amongst the industry’s most commonly respected and recognized certifications, CCNP would be setting you apart. It would be informing the world that you know about what you are doing. Also, completing any CCNP certification exam would have the ability to make you a Cisco Specialist certification to acquire recognition for your accomplishments along the way.

Advantages:

Seeing the world, you know your items with a high-value certification
Personalizing your certification to your technological focus
Positioning yourself for development in the hectic world of information center technologies
Adding information center automation skills to your areas of proficiency
Making a Specialist certification for clearing any CCNP examination — core or concentration
Receiving the CCIE Data Center lab exam by removing the CCNP core examination
Linking that CCNP certification badge to all your social media profiles

Here are a few of the job roles in addition to the Salary:

Network Administrator: AED 114k

Security Architect, IT: AED 390k

Network Architect: AED 192k

Systems Engineer (Computer Networking/ IT): AED 119k

Network Engineer: AED 87k

Sr. Network Engineer: AED 193k

Information Technology (IT) Manager: AED 131k

Suppose you wish to get the CCNP Data Center Certification and the job opportunities. In that case, you need to gain correct study products and likewise acquire the PASSHOT CCNP Data Center Exam Dumps. PASSHOT has assisted great deals of candidates to accomplish success in their highly first effort.

Can I pass CCNA without experience?

I think that acquiring a CCNA accreditation is the initial step to prepare for an IT innovation career. To get the CCNA certification, you need to clear an examination based on software application advancement skills, the latest network innovation, and task functions, covering IT careers’ broad fundamentals. CCNA offers you the basis for advancement in any direction.

You may want to enter an innovation profession. Otherwise, you may want to climb up. Networks, software, and facilities will be significantly interconnected. To sign up with a technology career in this quickly changing environment, you require to understand the current network innovation and automation, security, programmability, and working with supervisors, which needs your knowledge. CCNA accreditation will take you where you wish to go.

The CCNA examination will cover a large variety of subjects, including network access, network fundamentals, security essentials, IP services, IP connectivity, and automation and programmability. The CCNA training courses and examinations have actually been re-adjusted with the latest technologies and positions and will supply you with the basis for advancement in any instructions.

The industry’s most appreciated and recognized associate-member level accreditation, the CCNA process, could not be more simple. All you have to do is pass an examination, and after that, you can finish it.

Prerequisites

There are no formal requirements for CCNA accreditation, but you should comprehend the exam subject before the examination begins.

CCNA candidates normally likewise have:

– One year or more of experience in managing and implementing Cisco services

– Basic IP addressing understanding

– Fully understand the basics of the network

It is unneeded to have a CCNA experience, but it is suggested that you understand a specific field.

Obtained CCNA accreditation

The CCNA program supplies you with extensive associate-level training and certifications that will focus on the technologies needed to manage and execute networks and IT infrastructure.

The CCNA accreditation just requires one exam, that is, 200–301 Cisco Certified Network Assistant (CCNA). This test will cover broad standard knowledge in any direction you want to attain. The management and application courses of Cisco Solutions (CCNA) can help you get ready for passing exams through hands-on laboratory practice to enhance practical work abilities.

In conclusion

Now that you have gotten in-depth information about the CCNA certification, and you may want to succeed with one effort. It is suggested that prospects get a dump of the PASSHOT CCNA examination to prosper in the very first attempt.

What jobs pay a million dollars a year?

1. Big Data engineer

Organizations need individuals who can alter many unrefined details into important information for strategy setting, vibrant, and development — and compensate somewhat for individuals with these capabilities. The settlement midpoint (or mean public payment) for big details engineers is $166,500. These specialists usually make an organization’s product, equipment engineering, and frameworks that people require to work with the information. Substantial info styles typically have a degree in software application engineering and ability in math and information sets.

2. DevOps Engineer

DevOps engineers are the extension of coding and creating. To procure a midpoint compensation of $120,000, these experts work throughout departments to help increment a company’s efficiency by developing and improving different IT frameworks. DevOps styles regularly need insight with coding dialects, programming and security structures, solid clinical, critical thinking, and collaboration abilities.

3. Information systems security supervisor

Presently like never before, managers need gifted IT security experts to help guard touchy info and frameworks. These IT stars similarly need to remain aware of security patterns and government guidelines. Bosses frequently require affirmations like the Certified Information Systems Security Professional (CISSP), CompTIA Security+ or Cisco CCIE Security.

4. Mobile applications developer

Take a gander at your telephone or tablet applications, and it’s effortless to figure out why portable applications engineers are searched for. These IT geniuses need the skill to create applications for well-known stages, like iOS and Android. They furthermore must have experience coding with flexible structures and portable improvement dialects and details on web improvement dialects. The settlement midpoint for versatile applications designers is $135,750.

5. Applications architect

Regardless of considerable specialized capacities, applications designers require to operate very well in groups — and here and there supervise them. This is one of the most lucrative IT jobs since every company needs to enhance existing applications or make brand-new ones.

6. Data architect

They interpret organization prerequisites into details base arrangements and handle info stockpiling (server farms) and how the statement has collaborated. The compensation midpoint for info modelers is $145,500.

Many other IT jobs might earn you a million dollars per annum; thus, to have more on this, you can likewise visit us on PASSHOT IT Exam Dumps, where you would find extensive information on this. When it concerns the preparation of IT Exams, PASSHOT IT Exam Dumps are the very best ones.

How to use 802.1X protocol to solve network internal loopholes

Today we will consolidate the concept and application of the 802.1X protocol.

In traditional corporate networks, it is generally believed that the corporate intranet is safe, and threats mainly come from outsiders. But in fact, the internal loopholes in the network damage the network more seriously.

In addition, internal employees lack security awareness and malicious software such as various plug-ins, spyware, and Trojan horse programs will unknowingly be downloaded to the computer and spread on the corporate intranet, creating serious security risks. With the continuous escalation of security challenges, traditional security measures alone are no longer enough. You should consider starting with the security control of the terminal connected to the network, and the security status of the terminal and the network.

802.1x is mainly based on Client/Server access control and authentication protocol. It is mainly used to restrict unauthorized users from accessing the LAN/WLAN network through the access interface. 802.1x authenticates users connected to switch ports. After the authentication is passed, normal data can pass through the Ethernet port smoothly. It is an interface-based network access control method.

802.1x includes three entities of the client, the device and the authentication server.

The user terminal for 802.1x authentication is usually the user, who initiates the 802.1x authentication by starting the client software. Generally, it is an entity located at one end of a LAN link and is authenticated by a device at the other end of the link.

The device side usually refers to a network device that provides an interface for the client to access the LAN and supports the 802.1x protocol. Used to authenticate the client.

The authentication server is used to authenticate, authorize, and account for users, and is usually a RADIUS server. An entity that provides authentication services to clients.

802.1x supports port and MAC-based authentication mode. When the port-based mode is adopted, as long as the first user under the port is successfully authenticated, other access users can use network resources without authentication. But when the last user goes offline, other users will also be denied access to the network. If the MAC address-based mode is adopted, all access users under this port need to be authenticated separately.

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Best PSTN protocol introduction

PSTN (Public Switched Telephone Network) is a switched network used for global voice communications. This network has approximately 800 million users and is the largest telecommunications network in the world today.

In normal life, such as when we use a landline phone to make a call or use a telephone line to dial the Internet at home, we all use this network. One thing that needs to be emphasized here is that the PSTN network existed for the transmission of voice data from the beginning.

PSTN (PublicSwitch Telephone Network) is a telephone network commonly used in our daily lives. As we all know, PSTN is a circuit-switched network based on analog technology. Among many wide area network interconnection technologies, the communication cost required for interconnection through PSTN is the lowest, but its data transmission quality and transmission speed are also the worst, and the PSTN network resource utilization rate is relatively low.

It also refers to POTS. It is a collection of all circuit-switched telephone networks since Alexander Graham Bell invented the telephone. Today, except for the final connection between the user and the local telephone switchboard, the public switched telephone network has been technically fully digitalized.

In relation to the Internet, PSTN provides a considerable part of the long-distance infrastructure of the Internet. In order to use the long-distance infrastructure of the PSTN and share the circuit through information exchange among many users, the ISP needs to pay the equipment owner a fee.

In this way, Internet users only need to pay the Internet service provider. The public switched telephone network is a circuit-switched service based on standard telephone lines, used as a connection method for connecting remote endpoints. Typical applications are the connection between remote endpoints and local LAN and remote users dial-up Internet access.

PSTN can be composed of two parts, one is the switching system; the other is the transmission system, the switching system is composed of telephone switches, and the transmission system is composed of transmission equipment and cables. With the growth of user needs, these two components are constantly developing and improving to meet user needs.

1. The development of the exchange system probably goes through the following stages.

In the era of manual switching, transfers are performed manually. Just like a long time ago, when making a call, an operator will be connected first, and the operator will help you with the transfer.

In the era of automatic switching, step-by-step and crossbar switches were produced.

In the era of semi-electronic switching, electronic technology was introduced into the control part of the switch.

In the era of air division switching, program-controlled switches were created, but analog signals were still transmitted.

In the era of digital switching, with the successful application of PCM pulse code modulation technology, digital program-controlled switches have also been produced, in which digital signals are transmitted.

2. PSTN transmission equipment has evolved from carrier multiplexing equipment to SDH equipment, and cables have also evolved from copper wires to optical fibers.

What PSTN provides is an analog dedicated channel, and the channels are connected via several telephone exchanges. When two hosts or routers need to be connected via PSTN, modems must be used to implement signal analog/digital and digital/analog conversion on the network access side at both ends.

From the perspective of the OSI seven-layer model, PSTN can be seen as a simple extension of the physical layer, and does not provide users with services such as flow control and error control. Moreover, because PSTN is a circuit-switched way, a path is established until it is released, and its full bandwidth can only be used by the devices at both ends of the path, even if there is no data to be transmitted between them. Therefore, this circuit switching method cannot achieve full utilization of network bandwidth.

PSTN access to the network is relatively simple and flexible, usually as follows:

1. Access to the network through ordinary dial-up telephone lines. As long as the modem is connected in parallel on the original telephone lines of the two communication parties, and then the modem is connected to the corresponding Internet equipment. Most Internet devices, such as PCs or routers, are provided with several serial ports, and serial interface specifications such as RS-232 are used between the serial port and the Modem. The cost of this connection method is relatively economical, and the charging price is the same as that of ordinary telephones, which can be applied to occasions where communication is not frequent.

2. Access the network through leased telephone lines. Compared with ordinary dial-up telephone lines, leased telephone lines can provide higher communication speed and data transmission quality, but the corresponding costs are also higher than the previous method. The access mode of the dedicated line is not much different from the access mode of the ordinary dial-up line, but the process of dial-up connection is omitted.

3. The way to connect to the public data exchange network (X.25 or Frame-Relay, etc.) from PSTN via ordinary dial-up or leased dedicated telephone line. It is a better remote way to use this method to realize the connection with remote places, because the public data switching network provides users with reliable connection-oriented virtual circuit services, and its reliability and transmission rate are much stronger than PSTN.

How to configure voice VLAN with virtual local area network?

If you do yoga, meditate, smoke one by one, or eat a lot of refreshing food when you are nervous, please take a break and do so now, because frankly, the content is harder this time!

The voice VLAN function allows the access port to transmit voice data streams from IP phones. When a Cisco IP phone is connected to a switch, it will specify the Layer 3 IP priority and Layer 2 Class of Service (CoS) values in the voice data stream sent; for voice, these two values are both 5, and for For other data streams, the default is 0.

If the data transmission is uneven, the voice quality of the IP phone will be reduced, so the switch supports the quality of service (QoS) based on IEEE 802.1p CoS. 802.1p provides a mechanism to implement QoS at the data link layer. In the 802.1Q relay header, the information of the 802.1p field is included. Looking at the fields in the 802.1Q tag, you will see a field named “Priority”, which contains 802.1p information. QoS uses classification and scheduling to send network traffic from switches in an organized and predictable manner.

The Cisco IP phone is a configurable device that can be configured to include IEEE 802.1p priority in the data stream sent. The switch can also be configured to trust or override the priority assigned by the IP phone-this is exactly what we are going to do. A Cisco IP phone is basically a three-port switch: one is connected to the Cisco switch, one is connected to the PC, and another port is located inside, which is connected to the phone itself.

For the access port connected to the Cisco IP phone, it can be configured to use one VLAN for the voice data flow and another VLAN for the data flow of the device (such as a PC) connected to the phone. The access port of the switch can be configured to send Cisco Discovery Protocol (CDP) packets, and the connected Cisco IP phones can be instructed to send voice data streams to the switch in one of the following ways:

• Send via voice VLAN and add a layer 2 CoS priority value;

• Send via access VLAN and add a layer 2 CoS priority value;

• Send via the access VLAN, but do not add the layer 2 CoS priority value.

The switch can also handle tagged data streams (data streams with the frame type of IEEE 802.1Q or IEEE 802.1p) from devices connected to the access ports of Cisco IP phones. You can configure the layer 2 access port of the switch to send CDP packets and order the Cisco IP phone to set the access port connected to the PC to one of the following modes.

• Trust mode: For the data stream received through the access port connected to the PC, the Cisco IP phone does not make any changes to it, and allows it to pass directly.

• Untrusted mode: For IEEE 802.1Q or IEEE 802.1p frames received through the access port connected to the PC, the IP phone adds the configured Layer 2 CoS value to them (the default is 0). Untrusted mode is the default setting.

Configure voice VLAN

By default, the voice VLAN function is disabled; to enable it, you can use the interface configuration command switchport voice vlan. After the voice VLAN function is enabled, the default CoS priority of the port will be used when sending untagged data streams, and the CoS value of IEEE 802.1Q or IEEE 802.1p data streams is not trusted.

The following is the voice VLAN configuration guide.

• Voice VLAN can only be configured on the access port of the switch; the trunk port does not support voice VLAN, but you can configure it yourself.

• In order for the IP phone to communicate correctly, the voice VLAN must be configured and activated on the switch. To see if there is a voice VLAN, use the privileged EXEC command show v1an-if so, it will be displayed in the output of the command.

• Before enabling voice VLAN, it is recommended to use the global configuration command mls qos to enable QoS on the switch, and use the interface configuration command mls qos trust cos to set the trust status of the port to trust.

• CDP must be enabled on the switch port to which the Cisco IP phone is connected in order to send the configuration. CDP is enabled by default, so unless it is disabled, there will be no problems.

• After voice VLAN is configured, PortFast will be automatically enabled, but after voice VLAN is disabled, PortFast will not be automatically disabled.

• To restore the port to its default settings, use the interface configuration command no switchport voice vlan.

Configure the way the IP phone sends voice data streams

The switch port connected to the Cisco IP phone can be configured to send CDP packets to the IP phone to configure the way the phone sends voice data streams. The phone can send the voice data stream in IEEE 802.1Q frame, and include the layer 2 CoS value; IEEE 802.1p priority tag can be used to give higher priority to the voice, or it can be accessed through the VLAN instead of the native VLAN Transmit all voice. IP phones can also send untagged voice data streams through the access VLAN, or use their own configuration to send voice data streams. In all the above cases, the voice data stream contains a layer 3 IP priority value; for voice, this is usually set to 5.

Now it is time to provide some examples to give you a clear understanding of this. The following example demonstrates how to configure 4 aspects:

(1) How to configure the port connected to the IP phone so that it uses the CoS value to classify the incoming data stream;

(2) How to configure the port to use IEEE 802.1p priority to mark the voice data stream;

(3) How to configure the port to use voice VLAN (10) to transmit all voice data streams;

(4) Finally, how to configure VLAN3 to transmit PC data.

The command mls qos trust cos tells the interface to use the CoS value in the packet to classify the incoming data flow. For untagged packets, the default CoS value of the port is used. But before configuring the trust status of the port, you must use the global configuration command mls qos to enable QoS on the switch.

Note: Until I assigned the same port to two VLANs, I can only do this when one of them is a data VLAN and the other is a voice VLAN.