Home > PPP over Ethernet (PPPoE) Tutorial

PPP over Ethernet (PPPoE) Tutorial

February 29th, 2016 in ROUTE Knowledge Go to comments

PPPoE stands for Point-to-Point Protocol over Ethernet. It is a means of establishing a point-to-point communications channel over an Ethernet network. But why do we need PPPoE? To understand the reason of PPPoE, we need to understand about Ethernet and PPP.

As we know, Ethernet is not a point-to-point but a multipoint technology (even when two devices are connected back to back). Ethernet is designed to allow multiple devices to share a common medium, called a “broadcast domain”.

While Ethernet is dominating at customer sides, Internet Service Provider (ISP) still like PPP because of authentication (PPP supports CHAP), accounting (checking customer’s bill), link management (ISP can use PPP to assign a public IP address for customer).

However, Ethernet and PPP do not support each other natively. To utilize the benefits of both Ethernet and PPP, a protocol was created: PPPoE, which allows computers to connect to an ISP via a Digital Subscriber Line (DSL) modem.

 

PPPoE_Connection.jpg

PPPoE creates a PPP tunnel over an Ethernet connection by encapsulating a PPP frame inside an Ethernet frame. The modem converts the Ethernet frames to PPP frames by stripping the Ethernet headers. The modem then transmits these PPP frames on the ISP’s DSL network.

Note: PPPoE client functionality can be installed on the DSL modem or on the user computer as a software. If PPPoE is implemented on the DSL modem, all the users behind will share the same PPPoE account of the DSL modem. If PPPoE is installed on user computer, each computer can access different services with different PPPoE accounts. Nowadays PPPoE client functionality is available in most operating systems from Windows, Linux to Mac OS.

The picture below shows the PPPoE Client dialog box to enter username and password before making a PPPoE connection on Windows OS.
PPPoE_Client_Windows.jpg

PPPoE Client on Windows

PPPoE simulates the dial environment where each PPPoE session is treated as a separate phone line, even though they are being transported on a single PVC.

PPPoE is composed of two main phases:

+ Active Discovery Phase: In this phase, the PPPoE client locates a PPPoE server, called an access concentrator. During this phase, a Session ID is assigned and the PPPoE layer is established.
+ PPP Session Phase: In this phase, PPP options are negotiated and authentication is performed. Once the link setup is completed, PPPoE functions as a Layer 2 encapsulation method, allowing data to be transferred over the PPP link within PPPoE headers.

PPPoE Configuration

PPPoE_Topology.jpg

Configuration at Client side (PPPoE Client)

interface Dialer 2
 encapsulation ppp
 ip address negotiated
 ppp chap hostname TUT
 ppp chap password MyPPPoE
 ip mtu 1492
 dialer pool 1

1. First we need to create a dialer interface with the interface Dialer 2 command. Any interface number is good. A dialer interface is a virtual interface and PPP configuration is placed on the dialer interface, not on the physical interface. The PPPoE client can be configured with a static IP address but in most cases it will be automatically assigned a public IP address by the ISP so we used the ip address negotiated command here.

The CHAP hostname and password must be configured so that the PPPoE Server can authenticate the customer. The hostname and password configured on the PPPoE Client router must match the hostname and password configured on the PPPoE Server router. In this case, the commands ppp chap hostname TUT & ppp chap password MyPPPoE tells the router to use “TUT” & “MyPPPoE” as the username & password to authenticate with the server.

The maximum transmission unit (MTU) should be reduced to 1492 (default of 1500) to accommodate the PPPoE headers: 6 bytes for the PPPoE header and 2 more for the PPP protocol ID. This prevents unnecessary fragmentation.

Finally this dialer interface must be linked to a dialer pool with the dialer pool 1 command.

Next we configure the physical interface.

interface Ethernet0/1
 no ip address
 pppoe enable
 pppoe-client dial-pool-number 1

2. The physical Ethernet0/1 interface that connects toward the PPPoE Server is enabled PPPoE with the pppoe enable command. This physical interface is then linked to dialer pool 1 with the pppoe-client dial-pool-number 1 command. Notice that the dialer pool number must match on the dialer interface and physical interface. In other words, the number in the commands “dialer pool <number>” (on Dialer interface 2) and “pppoe-client dial-pool-number <number>” (on interface E0/1) must be the same. But notice that the dialer interface number (interface Dialer 2) does not have to match the dialer pool number. This is how the dialer pool is connected to the interface dialer and physical interface:

dialer_interface_dialer_pool_physical_interface.jpgAlthough this way of configuration is a bit more complex than directly connecting physical interfaces into dialer interface but it makes the configuration more flexible. Imagine you have three dialer interfaces 2, 5, 10 and many physical interfaces. With dialer pools, you can easily change the physical interfaces which need to associate with your dialer interfaces without making change at the physical interface level.

multiple_dialers.jpg

In the next part we will learn how to configure PPPoE at Server side.

Comments
Comment pages
1 2 3 1472
  1. Anonymous
    April 18th, 2017

    HI everyone,
    Can anyone please share dumps . mtowhidulislam1 at gmail dot com

  2. Anonymous
    April 19th, 2017

    hi guys…..can s0mebody please send me latest route dumps
    {email not allowed}
    Many thanks guys

  3. Anonymous
    April 19th, 2017

    latest route dumps please send to zhawaz at gmail dotcom

  4. Gayatri
    April 24th, 2017

    Hi Guys,
    Kindly share me the latest route dumps as i am planning to give route exam in 2 weeks.
    Thanks in advance

  5. Gayatri
    April 24th, 2017

    Hi Guys,
    Kindly share me the latest route dumps as i am planning to give route exam in 2 weeks.
    gk.kundum2013 at gmail dotcom
    Thanks in advance

  6. Oluwashina
    April 30th, 2017

    Any latest dumps please kindly forward it to: Oluwashinasamson67 @ gmai. Com
    10ks

  7. Ali113
    May 3rd, 2017

    Hi,
    kindly share me latest route dumps. {email not allowed}
    thanks.

  8. Ali113
    May 3rd, 2017

    kindly share me latest route dumps.
    at alimahmood88 @gmai. COm

  9. Anonymous
    May 7th, 2017

    Hi Guys,
    Could anyone kindly share with me latest route dumps 300-101, 300-115, 300-115, as i am taking route exam in 3 weeks.
    hugoandrade73 at yahoo dotcom
    Thanks in advance

  10. Anonymous
    May 8th, 2017

    Can somebody share with any dumps {email not allowed}. Thanks

  11. Deeps
    May 29th, 2017

    Hello Guys anybody having the latest Route dumps please share it with me deepu13ra at gmail dot com

  12. Deeps
    May 29th, 2017

    Hello guys,

    i am planning to do this certification.
    Please send the latest dumps to this id is deepu13ram @gmail.com

  13. Stentah
    May 30th, 2017

    Hello,
    I have the exam in 3 weeks.
    Can someone please send me the latest dumps: stentah1010 AT gmail.com
    Thank you

  14. Anonymous
    June 1st, 2017

    Hello anyone, can you help me with the dumps Route and TSHOOT?

    My e-mail is: info AT anemosradio.com

    Thank you!

  15. icey
    June 4th, 2017

    hello can anybody plz send me the latest route dumps to “schd AT vodafone.de”
    very appreciated

  16. Anonymous
    June 6th, 2017

    Hi send me latest dumps on fatimazjafri at hotmail.com

  17. Richard w
    June 6th, 2017

    Did anyone take exam recently ? pls share the experience Thanks

  18. Anonymous
    June 6th, 2017

    Too questions news, I fail exam, the labs are still valid.

  19. Anonymous
    June 8th, 2017

    can someone Please send me new dumps {email not allowed}??

  20. Anonymous
    June 8th, 2017

    can some one please send me new dumps mikesesay2000 at yahoo.com

  21. Anonymous
    June 8th, 2017

    I have my exam three weeks from now please help me with dumps mikesesay2000 at yahoo.com
    thanks in advance

  22. Kato
    June 8th, 2017

    Pass the CCNP route 300-101 exame monday 5th june.

    The questions you can find in this site is good at least for the 50%.

    The lab are the same.

    But you have to study anyway.

    Good luck

  23. Anonymous
    June 9th, 2017

    @Kato could you please help me with some Materials and please send it to mikesesay2000 at yahoo.com

  24. adamcas
    June 13th, 2017

    I will take this exam in 3 weeks, anyone please share valid dumps at adamcas23 @gmail. com, I really appreciate it

  25. KAL-EL
    June 13th, 2017

    Hi, just passed 300-101 today. The labs are still the same, but about 30% of the questions were new to me (had not seen them in any dump). The focus of these questions were about EVN, PPPoE, DMVPN, NAT-PT, uRPF, SNMP, UDP and NTP. Good Luck!

  26. Juan
    June 15th, 2017

    Anyone want to share latest dump, I am taking it next week and appreciate the assistance. {email not allowed}

  27. Zaman
    June 18th, 2017

    Excellent document!!!

  28. Mercy
    June 19th, 2017

    Hey,
    @KAL-EL please kindly send me the dump that u used to prepare for the exam. My email address mercykamau2010 @gmail. com.

  29. Anonymous
    June 19th, 2017

    Hello,

    Could somebody send me the last dump of routing 300-101 at {email not allowed} please?
    Thank you.

  30. Anonymous
    June 19th, 2017

    Hello guys,

    Please, somedoby could send me the last dump of routing 300-101 at vinicius _ samy2 @yahoo .com .br?
    Thank you

  31. kkvanus
    June 21st, 2017

    please i want latest dump somebody send me. {email not allowed}

  32. Anonymous
    June 22nd, 2017

    Any one can please share the dumps parthparmar 755 at gmail.com of ccnp route

  33. Yrsillar
    June 26th, 2017

    Failed the route exam with 640 last june 23. Im planning to retake it.
    Labs are just the same.. lots of new questions. Please refer to @KAL-EL’s comment above regarding the new questions.

    Can someone send me some updated dumps? please send to my email – dlinuxuser1 @ gmail

    Thank you and good luck to all who will be taking the exam.

  34. Anonymous
    June 30th, 2017

    Hey Guys can u please send the latest dumps on miguelfilipe_20_01 @ hotmail . com

  35. Anonymous
    June 30th, 2017

    Hi can someone please send the latest route dump to ron davis at gmail

  36. marcus
    July 3rd, 2017

    please share latest dumps, realmarcus.com at gmail dot com

  37. Chocolate
    July 4th, 2017

    hello, please send the latest dumps on barebon2005 @ yandex . ru

  38. Anonymous
    July 8th, 2017

    could somebody send me new dump at keveave @ yahoo . com please?

  39. gogochocolate
    July 9th, 2017

    please could anyone share the latest dumps with {email not allowed}. thanks alot

  40. gogochocolate
    July 9th, 2017

    please could anyone share the latest dumps with ilikaugochukwu @ gmail.com

  41. kal
    July 11th, 2017

    Please Send me the Valid Dumps of CCNP 300-101 at mail {email not allowed}

  42. kal
    July 11th, 2017

    Please Send me the Valid Dumps of CCNP 300-101 at mail kalyanvaishnav at gmail.com

  43. Nk
    July 12th, 2017

    Pls share CCNP 300-101 with nag_knaveen at yahoo.com

  44. jokie
    July 13th, 2017

    Thanks for you share,if you download vce,pdf for 300-101 http://www.exam.com/300-101.html

  45. beatrice
    July 14th, 2017

    Hi guys,I am about to write my Routing and I really need your help.I need the RECENT Dumps for my exam. This is my email {email not allowed}. Thanks in advance

  46. farid
    July 18th, 2017

    Hi guys, I am going to take CCNP ROUTE – 300-101 exam soon. Please share your experiences and send latest dumps to {email not allowed}.

  47. adam
    July 18th, 2017

    Please share latest dump 301-101 with adamcas23 @ gmail.com
    I am going to take exam soon :(

  48. dj
    July 20th, 2017

    can any share Dumps 300-101(CCNP routing , switching , tshoot) with {email not allowed}. Thanks in advance. i will be really appreciate for this .

  49. dj
    July 20th, 2017

    can any share Dumps 300-101(CCNP routing , switching , tshoot) with dhe e r aj. bansal @ gm a i l .c o m . just ignore spaces.Thanks in advance. i will be really appreciate for this .

  50. snx
    July 28th, 2017

    hi all,
    highly appreciate if you can share the latest dump to ssp (dot) lesson @ gmail (dot) com
    Thank you very much.

  51. Rgalvan
    August 1st, 2017

    Hello all, Next month I will take the CCNP 300-101 exam. Could someone share latest dumps?

    Thanks

  52. Rgalvan
    August 1st, 2017

    Muy email is rgalvanhe at gmail.com

  53. ADEL ALYOUSEF
    August 2nd, 2017

    Hi,
    Can you send me the lates dump for 300-101 to my email AAALAAA @ LIVE .COM ?

    Thanks all.

  54. adamcas
    August 4th, 2017

    Anyone please share latest dump to my email adamcas23 @ gmail.com
    Thank you very much

  55. Adam_Q
    August 6th, 2017

    They say it is 484q must be the latest dumps. Could anyone share it to me please
    slipkors @ yahoo . com

  56. Vender
    August 7th, 2017

    Latest 100% VALID passing Material
    CCNA 200-125 LAtest Dumps
    CCNP ROUTE 300-101 Latest
    CCNP SWITCH 300-115 LAtest
    CCNP TSHOOT 300-135 LAtest
    CCIE R&S 400-101 LAtest

    https://docs.google.com/document/d/1cp2vtCYSV_21JTZF9D14Ua2gHdijtZjfIDuyVT1NyJg/edit?usp=sharing

    For Any support moeez.dean h-o-t-m-a-i-l-.-c-o-m

  57. adam9988
    August 8th, 2017

    Anyone please share latest dump to my email gihan9988 at gmail dot com.
    Thank you very much

  58. Mess
    August 10th, 2017

    I am going to take the exam next month. Please share the latest dumps at epokdohrg1 @ yahoo . com…I appreciate it. Thank you!

  59. Sang
    August 14th, 2017

    Hi,
    Could anyone send me CCNP(route,switch,tshoot) lastest dumps please.
    {email not allowed}

  60. Sang
    August 14th, 2017

    Hi,
    Could anyone send me CCNP(route,switch,tshoot) lastest dumps please.
    hallo-84 @ hanmail.net

  61. Anonymous
    August 20th, 2017

    Hello,
    Can someone please send me the newest CCNP Route dumps. Thank you so very much in advance jettttstream @ gmail com.

  62. mozem
    August 21st, 2017

    please can you send the recent ccnp route dumps: sylvester . nzemo at yahoo.fr

  63. Download-Instant
    August 21st, 2017

    We have All Dumps on this site:

    ICND, CCNA , CCNP, CCNA Security , CCNA Voice , CCDP , CCDA , CCNP , CCIE

    100% Valid Dumps Available Here PDF + VCE Both Files

    Instant-Download:
    https://docs.google.com/document/d/1cp2vtCYSV_21JTZF9D14Ua2gHdijtZjfIDuyVT1NyJg/edit?usp=sharing

  64. Brad
    August 22nd, 2017

    Guys, could you please share latest dumps: janec . p at tiscali.cz Thank you a lot for your help.

  65. Anon
    August 24th, 2017

    Please send me latest Route Dumps Please!!!!!!!!! at u2010151 at gmail .com

  66. Tan
    August 24th, 2017

    Awesome … like this doc. Keep it up, buddy.

  67. Anonymous
    August 25th, 2017

    Failed today with 760pts….although I cleared all my labs , loads of new questions ,don’t trust any dumps…study hard chaps….and loads of simlet ( IPV6 , ACL, NAT, NAT-PT ETC ETC )

  68. Tam
    August 25th, 2017

    HI Tan can you give me also the dumps for 300-101 at my email {email not allowed}

  69. Netw
    August 25th, 2017

    If you want gns3 lab for mpls vpnv4, check this
    https://garziadmostafa.wordpress.com/2017/08/21/mpls-vpnv4-configuration/

  70. Anonymous
    August 27th, 2017

    Please kindly share the recent dumps for ccnp route pleas, will really appreciate

  71. Steve
    August 30th, 2017

    Please send me the newest dumps via mail

    milenkovic23 @ hotmail . com

    Thank you.

  72. Anonymous
    September 3rd, 2017

    Hi guys,I am about to write my Routing and I really need your help.I need the RECENT Dumps for my exam. This is my email bimboy.conde at yahoo com Thanks in advance

  73. Anonymous
    September 4th, 2017

    Please email me the latest dumps. freyjasbooks at gmail com

  74. New470Qs
    September 12th, 2017

    Passed. 9xx…
    McQs: 3 or 4 new quesitons
    Labs all: same
    Drag and Drop: same
    Dumps470Qs

    https://docs.google.com/document/d/1cp2vtCYSV_21JTZF9D14Ua2gHdijtZjfIDuyVT1NyJg/edit?usp=sharing

    All exam questions are cover with Lab simulation and Drag drop in above link.
    Thankyou

  75. Anonymous
    September 13th, 2017

    kababakaramoko @ gmail . com please send me the last dump

  76. Anonymous
    September 25th, 2017

    Hi everyone,
    Could anyoven send me last version of ccnp dump that still valid please

    erkandursun1225 at gmail dot com

  77. CiscoDaddy
    September 26th, 2017

    Does anyone know if this is in the exam route 300-101?

  78. Spark
    October 3rd, 2017

    Can you send me the lastest dumps for all ccnp:routing and switching. Pls send it to “youngspark at ymail dot com”

  79. Anonymous
    October 4th, 2017

    Can someone send me the latest dumps at {email not allowed}

  80. Anonymous
    October 4th, 2017

    Can someone send me the latest dumps at “jaravind1 at yahoo dot co dot in”

  81. Anonymous
    October 13th, 2017

    Hi everyone,
    Could anyone send me last version of ccnp dump that still valid.

    questionmaster34 @ outlook dot com

  82. HIfly
    October 15th, 2017

    can somebody send me latest dump for ccnp 300-101 . iam planning to sit next week,
    would be very help

  83. HIfly
    October 15th, 2017

    can somebody send me latest dump for ccnp 300-101 . iam planning to sit next week,
    would be very help
    hifly.mansoor at gmail.com

  84. sky
    October 16th, 2017
Comment pages
1 2 3 1472
  1. No trackbacks yet.