Cisco CCNA Voice Certification Exam Tutorial – Default Max Ephone and Ephone-dn and Configurations

Cisco CCNA Voice Certification Exam Tutorial – Default Max Ephone and Ephone-dn and Configurations
By [http://ezinearticles.com/?expert=David_Bombal]David Bombal

How many phones and directory numbers can be configured on Cisco Unified Communications Manager Express by default?

Answer: Zero!

Yes, by default, no ephones or directory numbers can register. Before doing anything else, the following configuration is required:

Router>enable

Router#configure terminal
Router(config)#telephony-service
Router(config-telephony)#max-ephones 4
Router(config-telephony)#max-dn 8

This allow up to 4 phones to register / be configured and 8 directory numbers.

If you don’t do this, the router will not allow ephones or ephone-dns to be created. Here is an example of what would happen:

R1(config)#ephone 1
ephone tag 1 exceeds max-ephones 0
R1(config)#ephone-dn 1
dn 1 exceeds max-dn 0

The maximum number of ephones and ephone-dns that can be configured is platform dependent. Here is an example of my router that can support 30 phones with up to 150 ephone-dns:

R1(config-telephony)#max-ephones ?
Maximum phones to support

R1(config-telephony)#max-dn ?
Maximum directory numbers supported

Cisco have a great document showing you how many ephones/dns are supported on specific platforms. Have a look [http://www.cisco.com/en/US/products/sw/voicesw/ps4625/products_device_support_tables_list.html]here

As an example, using CME version 4.3:
The 2801 supports 25 phones and 120 ephone-dns
The 2811 supports 35 phones and 144 ephone-dns
The 2821 supports 50 phones and 192 ephone-dns
The 3845 supports 250 phones and 720 ephone-dns

(There are others, please refer to the link above for a full list)

Cisco also recommend that you only enable the number of ephones and ephone-dns for the number you require, not the maximum the platform can support. The reason is that when a ephone / ephone-dn is created, it uses up memory on the router. Don’t just create them because you can! Create only what is required.

To your success!

David Bombal,

CCIE #11023, CCSI, CCDP, CCIP, CCNP, CCSP, CCVP, CCNA, CCDA

David has over 10 years experience in the IT industry and has been training in the Cisco market for over 8 years. He has worked with Cisco IP Telephony since the Call Manager 3.0 days in 2001.

He is the owner of http://www.CCNAVoice.com which has many resources for the CCNA Voice candidate. Get access to free articles, eBooks, training and more. http://www.CCNAVoice.com also provides test questions and simulations to help you prepare for your studies, premium access to more detailed information and mentoring.

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CCNA Certification Exam Training: Circuit Switching vs. Packet Switching

CCNA Certification Exam Training:  Circuit Switching vs. Packet Switching
By [http://ezinearticles.com/?expert=Chris_Bryant]Chris Bryant

CCNA certification exam training is all about learning the details, and an important part of your CCNA test prep is knowing the differences between Cisco router and switch technologies that are somewhat similar.  Packet switching and circuit switching are both methods of getting packets from “point A” to “point B”, but the methods used are very different – and you must know these differences to earn your Cisco CCNA certification.

In my last CCNA training tutorial, I discussed packet switching.   In case you missed that article, packet switching is a method of transporting packets from source to destination via different paths; that is, the packets will not necessarily share the same physical path.  The packets are put into their proper order at the destination.  Packet switching is highly effective, but should not be used for delay-sensitive traffic such as voice or video packets.   Not only is Frame Relay a big topic for your CCNA exam, it’s also an excellent example of a packet-switching technology.

In circuit switching, a dedicated path is built between the source and destination, and the packets will all be sent over this dedicated path.   If this sounds like a telephone call, you’re right!  A phone call is a great example of circuit switching.  On a Cisco router, ISDN is a circuit-switching technology.

The deciding factor between circuit switching and packet switching comes down to the tolerance for delay.  Not to say that packet switching is slow, but any reassembly takes time.  While most packet-switching technologies are cheaper to run than most circuit-switching technologies, that cost is offset by the slight delay inherent to packet switching.  For voice and video, circuit switching is the most effective.

Packet switching and circuit switching both have their place in today’s Cisco networks, and don’t be surprised if both topics show up on your CCNA certification exam as well!

Chris Bryant, CCIE #12933, is the owner of The Bryant Advantage, home of over 100 free certification exam tutorials, including <A target=”_new” href=”http://www.thebryantadvantage.com/”>Cisco CCNA certification test prep</a> articles. His exclusive <A target=”_new” href=”http://www.thebryantadvantage.com/UltimateCCNAStudyPackage.html”>Cisco CCNA study guide and Cisco CCNA training </a> is also available!

Visit his blog and sign up for Cisco Certification Central, a daily newsletter packed with CCNA, Network+, Security+, A+, and CCNP certification exam practice questions! A free 7-part course, “How To Pass The CCNA”, is also available, and you can attend an in-person or online  <A target=”_new” href=”http://www.thebryantadvantage.com/CCNACCNPOnlineAndInPersonBootCamp.htm”>CCNA boot camp</a> with The Bryant Advantage!

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Cisco CCNP Certification Exam Training For The ONT Exam – QoS Models

Cisco CCNP Certification Exam Training For The ONT Exam -  QoS Models
By [http://ezinearticles.com/?expert=Chris_Bryant]Chris Bryant

A large part of your CCNP training for the ONT certification exam should be spent studying the various ways we can implement Quality of Service (QoS) on Cisco routers and switches.  Before you start configuring your network’s devices, though, you’ve got to understand the three QoS models and their impact on your network.  Let’s take a look at the pros and cons of each.

If you don’t have a QoS model in place, you actually do.  Best-effort QoS is just that – best-effort.  No priority is given to any traffic.  If your network is carrying voice or video traffic, best-effort is definitely not the way to go.

The Integrated Services model, more popularly known as IntServ, uses the Resource Reservation Protocol (RSVP) to reserve network resources in advance of the data actually traveling across the network.  Once the end-to-end bandwidth reservation is in place, the data is transmitted.

That sounds great, but there are some drawbacks.  It’s a waste of bandwidth to have the entire end-to-end path reserved in advance.  Additionally, IntServ isn’t as scalable a solution as we’d like.  Everything we do on a router or switch has a cost of some kind, and in this case it’s RSVP overhead.  One or two paths won’t cause much overhead, but as the number of reserved paths increases as a network becomes larger, the RSVP overhead can take its toll on the routers involved.

Differentiated Services (DiffServ) is the latest of the three models, and many would agree that it’s also the greatest.  DiffServ doesn’t use RSVP, but instead uses Per-Hop Behavior (PHB) to allow each router across the network to examine the packet and decide what service level it should receive.  With DiffServ, one router along the path from source to destination could consider a packet to be of the highest priority, while another router could consider it “just another packet”.

A term you hear often with DiffServ is “marking and classification”.  Marking a packet is the process of assigning the packet a value reflecting the level of QoS it should receive, while classification is placing that packet into a queue in accordance with that level of QoS.

When it comes to marking, there are different values we can use to decide what value to mark the frame or packet with.  In my experience, here are the four that are used most often:

•    IP Precedence (IP Prec)

•    Differentiated Services Code Point (DSCP)

•    CoS value

•    Interface that received the data (ingress interface)

Which one you choose depends on your particular network’s needs, and of course, the OSI layer at which the marking is taking place.  We’ll take a look at each of these methods in future CCNP ONT exam training tutorials!

Chris Bryant, CCIE #12933, is the owner of The Bryant Advantage, home of free <A target=”_new” href=”http://www.thebryantadvantage.com/CCNPTrainingStore.htm”>Cisco CCNP Training</a> and  <A target=”_new” href=”http://www.thebryantadvantage.com/”>CCNA Exam Training </a> tutorials, The Ultimate CCNA Study Package, and Ultimate CCNP Study Packages.

You can also visit his blog, which is updated several times daily with new Cisco certification articles, free tutorials, and daily CCNA / CCNP exam questions!

Visit his blog and sign up for Certification Central, a daily newsletter packed with CCNA, Network+, A+, and CCNP certification exam practice questions.    A free 7-part course, “How To Pass The CCNA”, is also available.

Earn your
<A target=”_new” href=”http://www.thebryantadvantage.com/MicrosoftWindowsVistaCertification.htm”>Microsoft Server 2008 certification</a> with The Bryant Advantage!

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Cisco CCNA and CCENT Certification Training – 10 Frame Relay Practice Exam Questions

Cisco CCNA and CCENT Certification Training – 10 Frame Relay Practice Exam Questions
By [http://ezinearticles.com/?expert=Chris_Bryant]Chris Bryant

Frame Relay is a major topic on your CCNA and CCENT certification exams, and for good reason. Frame Relay is a part of just about every Wide Area Network (WAN) you’ll ever work with, and you’ve got to know how to configure and troubleshoot FR to be successful in the exam room and your job.

To help you pass the CCNA and CCENT exams and be prepared for real-world success, here are 10 free Cisco certification exam training questions on Frame Relay. Some have choices, some do not – after all, there’s no multiple choice at the command line!

1. Your Frame Relay provider is guaranteeing you a certain amount of bandwidth that will be available to you at any given time. What acronym is used to describe that guaranteed bandwidth?

A. DE

B. CIR

C. LMI

D. BECN

E. FECN

2. A Frame Relay cloud consists of what device types?

A. Frame Relay switches acting as DCEs

B. Frame Relay switches acting as DTEs

C. Frame Relay routers acting as DCEs

D. Frame Relay routers acting as DTEs

3. Which of the following terms describes Frame Relay?

A. packet-switching

B. circuit-switching

C. relatively inexpensive when compared to other WAN connectivity methods

D. relatively expensive when compared to other WAN connectivity methods

4. What message types serve as keepalives between the DTE and DCE?

A. LMI

B. DLCI

C. DE

D. CIR

5. Short answer: What is the default encapsulation type of a Cisco router Serial interface?

6. Short answer: When LMI Autosense is in effect, what message type(s) does the DTE send to the DCE?

7. Short answer: When LMI Autosense is in effect, what message type(s) does the DCE then send to the DTE after receiving the message(s) referred to in question 6?

8. What command resulted in the following output?

LMI Statistics for interface Serial0 (Frame Relay DTE) LMI TYPE = ANSI

Invalid Unnumbered info 0       Invalid Prot Disc 0

Invalid dummy Call Ref 0       Invalid Msg Type 0

Invalid Status Message 0       Invalid Lock Shift 0

Invalid Information ID 0       Invalid Report IE Len 0

Invalid Report Request 0       Invalid Keep IE Len 0

Num Status Enq. Sent 121     Num Status msgs Rcvd 94

Num Update Status Rcvd 0       Num Status Timeouts 26

A. show frame pvc

B. show frame lmi

C. show frame timeouts

D. debug frame lmi

9. What command resulted in the following output?

R1#

3d04h: Serial0(out): StEnq, myseq 49, yourseen 94, DTE down

3d04h: datagramstart = 0xE329E4, datagramsize = 14

3d04h: FR encap = 0×00010308

3d04h: 00 75 95 01 01 00 03 02 31 5E

A. show frame pvc

B. show frame lmi

C. show frame dte

D. debug frame lmi

10. Short answer: What protocol enables dynamic Frame Relay mapping?

Here are the answers! No peeking!

1. (B). That’s the Committed Information Rate – the CIR.

2. (A). A Frame Relay cloud consists of Frame Relay switches, and those are DCEs.

3. (A, C). Frame Relay is a packet-switching protocol, and one major advantage of Frame is its cost – it’s relatively cheap!

4. (A). The Local Management Interface sounds like some kind of GUI, but it’s not. Among other functions, the LMI serves as a keepalive between the DTE and DCE. If there’s an LMI mismatch, the physical interface will remain up but the line protocol will go down.

5. The default encapsulation type of a Cisco Serial interface is HDLC, as verified here with show interface serial0. This particular interface is shut down, but the default encapsulation type still appears in the command output.

R1#show int serial0

Serial0 is administratively down, line protocol is down

Hardware is HD64570

MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,

reliability 255/255, txload 1/255, rxload 1/255

Encapsulation HDLC, loopback not set

6 & 7. When LMI Autosense is in operation, the DTE will send three LMI Status messages. The DCE will respond with one LMI Status message. The DTE sees that Status message coming in, and from that point on only sends the LMI Status message type that matches the type it received from the DCE.

8. (B) That output is the result of running the show frame lmi command. An excellent starting point for Frame Relay troubleshooting.

9. (D) That output is the result of running debug frame lmi. Always be careful when running debugs in a production network – never run a debug unless you’re sure of the resulting output, which can overwhelm the router.

10. Inverse ARP enables dynamic Frame Relay mapping. Inverse ARP is often disabled in today’s networks, and this is done by running the no frame-relay inverse-arp command at the interface level.

Look for more Cisco certification exam practice questions on this website!

Chris Bryant, CCIE #12933, is the owner of The Bryant Advantage, home of free <A target=”_new” href=”http://www.thebryantadvantage.com/”>CCNA</a> and <A target=”_new” href=”http://www.thebryantadvantage.com/”>CCNP exam</a> tutorials, The Ultimate CCNA Study Package, and Ultimate CCNP Study Packages.

Visit his blog, which is updated several times daily with new Cisco certification articles, free tutorials, and daily CCNA / CCNP exam questions!

A free 7-part course, “How To Pass The CCNA”, is also available.

Get your
Cisco CCNP Boot Camp with this special from The Bryant Advantage!

Article Source: http://EzineArticles.com/?expert=Chris_Bryant http://EzineArticles.com/?Cisco-CCNA-and-CCENT-Certification-Training—10-Frame-Relay-Practice-Exam-Questions&id=1242011