How to configure PPPOE connection. How to configure PPPOE connection. Configure PPPoE on the router. Setting the WAN interface of the router. Choice in the PPPoE list

Connection protocols, created with a single goal - to transfer digital data when connecting to the Internet, between two access points. There are not many such protocols as it may seem, users faced them not too often, since the choice of the type of connection is the prerogative of the provider. Internet service provider server is the first point, PC, smartphone, or any other device for connecting - the second.

The connection occurs due to the operation of switches, repeaters, or USB modems, and connects all the elements into the inseparable chain of the protocol, the efficiency and speed of the connection depends on it. One of these and is RPRO, belonging to the most common. This type prefers most Russian and world providers. Actually, compared to others, it is not too different, while maintaining the same principles of work, the main difference is only in their settings.

general information

In the literal translation of the decoding of the abbreviation PPPoE from English, it turns out not a very intelligible "Internet connection protocol between points." For an inexperienced user, it says little about what. The Russian translation of the Point-to-Point Protocol Over Ethernet sounds simplified, but extended, with a more comprehensive definition: "Internet communication protocol in networks, with a principle of point to point," and still information that clarifies the overall picture gives not much .

Using technical terminology is quite difficult to explain what kind of ppure general features - This is a tunneling focus protocol, setting up an IP address via the Internet using its own programs, to set the direct access point of the connected device with a signal source. That is, if it is easier - carries out uninterrupted transmission and processing Information between the computer and the provider server. The basis is the principle remote access (Dial Up), the only difference between them is a telephone line, otherwise the process occurs similarly.

Although the principle of all protocols one, the RPRO has its own characteristics, and the expansion of its capabilities, creates a number of advantages compared to other types of compounds, for example, such as L2TP, which uses in Russia, mostly Beeline. Due to this, he has such distribution and popularity:

  • first distinctive trait - Easy I. convenience in settings, managing and handling.
  • data compression occurring when they are transmitted, accelerating connection And the whole process.
  • availability of authentication At the entrance that protects against unauthorized penetration.
  • the multi-platform entity of the protocol providing him with unlimited possibilities.
  • data encryptioncarried out without damning throughput.
  • high levels of stability to characteristic failures and network errors.
  • which is happening in the shortest possible time.
  • most low cost, among other protocols.

what concerns shortcomings Rye, it is not very convenient in a bundle with routers, due to bad compatibility With an IPOE (connection at which you do not need to enter a login and password) using it to connect to the provider switch. In the case of using the Path MTU Discovery router, it creates the prohibition of ICMP packet fragmentation and their deviation. In other words, the system will give an error, and the connection will be broken.

Principle of operation

The main principle of work on the point to the point implies the establishment of contact between them, by connecting the user of the user and the provider server, through the Internet.

It happens in several stages.

On the initial, network cards of opposite points exchange MAC addresses for recognition, sending a request signal received by all network participants. They do not participate in this process, only supporting the service corresponds, that is, the desired one. In response, the access package is sent, but since at the same time there are many users using the same protocol, the PC takes not one, but a great set of packages. РРРуй software recognizes and chooses The desired of them, and together with the required data for the input, returns back.

At the next stage, if all IP addresses match, the DHCP server moves to the creation of the chain between the two points. Package starts from the client applied software (RRP) participating in the overall process and using most protocols. After receiving the session identifier, the server and the client gets up virtual tunnelThe connection and packaging of IP traffic in RWP packets is installed. The oncoming data exchange streams do not slow down the system, but on the contrary unload it to the fact that the transmission is carried out in separate channels, and the connection to occur almost instantly.

Minimports

A fairly frequent phenomenon, when attempting to connect to the network using RPRO, is "Error 651" which occurs on Win7 / 8. It is also called an error of connecting via Wan Miniport PPPoe (the name is used to designate an error, and some specific value does not have). Her elimination, the task is not easy, often does not help and reinstall the operating system. The complexity arises in identifying the problem, it can be wounded in network equipment and user, and provider.

Frequent causes of error and ways to eliminate it:

  1. Failure in work RasppPoE - services that controls the "high-speed connection". In this case, reconnection will be required by removing the newly created and create a new, using the user name and the password that opens access.
  2. The connection blocks not recognizing his firewall, or antivirus program. Here everything is solved much easier - disabling. In the case of a built-in firewall, its work turns off completely, even if this is not recommended. As for the antivirus, the program is turned off without protection itself, but only the network screen.
  3. Wrong workADSL modemaMaintains an error if it is configured as RPRY instead of Bridge, or the VPI and VCI parameters are incorrectly specified. At the same time, the problem with the connection is eliminated by the modem to the reconfiguration, using the correct data and the maximum concentration of attention when making them.

The same applies to the failure of the router, or incorrect settingssimilar to an ADSL modem - will have to re-configure it. These are the most common, but far not the only reasons Errors, also they can be in malfunction of a telephone pair, damage to the Internet cable, or proceed from the provider. This must be clarified, first of all, in the service technical support Network service provider.

Features

Among those, the technology is allocated, transmitting data to ether with wireless way through radio communications. Using a separate line It is considered more reliable, but it does not always create a favorable environment for connecting, and is too expensive for the client.

Modem connection At all, do not belong to reliable, it can break into any time, and the speed leaves it to be desired. Thus, radio communication used for connection via the RPRO protocol is more reliable than any other.

Settings

This is a completely difficult process, accessible and inexperienced users who have not previously implemented. Independently, where the connection is configured by PPPoE protocol on operating system or router, it is important to do everything in the correct sequence, naturally every device has its own.

On the computer (for win7)

Two-related OS 7 and 10, PPPOE settings are somewhat different:

  1. In the "Start" menu, choose " Control Panel"And go to her double left click.
  2. In the upper left corner choose "Network and Internet".
  3. He redirects to the "Network Management Center ...".
  4. Go to folder with " New connection settings».
  5. In the pop-up window, select "Internet connection" - "Next".
  6. The system will notify that the connection is made, click "Create a connection anyway".
  7. From the proposed options, notice "high-speed (with RPRO)".

The tab " Connections"Where you need to fill out all the fields, indicating the data provided by the provider in the contract and confirm them by clicking on" Connect ". It will occur immediately as the system will authenticate.

For Windows 10.

When using 10 version, the connection is slightly different, only in detail:

  1. In the "Start" menu, choose " Parameters"And go to them.
  2. On the settings panel, open "Network and Internet" - "Internet".
  3. After redirecting, click on " Create and configure connection».
  4. Among the proposed options, select "Connection" - "Continue".
  5. In a new window, note "high-speed (with RPRO)."

Further, all occur in the same way as for Win7.

On Linux

IN settings Linux The procedure is fundamentally different, here it happens with the help of the utility " pPPOECONF."But available only with the superuser's rights. To configure, apply such actions:


On Debian.

Here everything happens similarly to the previous one.

On FreeBSD.

In this case, the entire sequence of actions comes down to filling out the necessary data provided in the contract with the provider in the ETC / PPP / PPP.Cont file:

  1. Name configuration to set the connection.
  2. Specify the network interface, To connect the cable.
  3. Register login and password from the contract.
  4. Confirm the entered data.

After that, the configuration and connection occur in automatic mode.

On router

To configure the connection on the router, first it will be necessary to connect it - Internet cable to (yellow) LAN-port, and service provider cable to (blue) WAN-port. You can then go directly to the router settings:

  1. In the "Start" menu, open the "Control Panel" where to choose " Network and Internet».
  2. Go from the "Network Management Center ..." to "Manage Network Connections".
  3. Choose in " Connecting in local network "-" Properties "and" Protocol version 4 ".
  4. Here, mark the addresses automatically for IP and DNS.
  5. In the browser search bar, type the router IP address specified on its bottom panel.
  6. In the window that opens, enter the default login and password (usually Admin and Admin).
  7. In the web interface of the router to select "Network" - "WAN" and option " PPPoE /Russia.».
  8. Save changes and restart the router.

Connection removal

To remove the ppure compound, 3 methods are provided.

Through the "Control Panel"

The easiest - use the control panel:


Through the "Device Manager"

You can use the Device Manager:


Through the string "Run"

You can use the command interpreter "Run":

  1. It is familiar through the "Start" menu to open the line panel " Perform».
  2. Here to introduce the value " regedit."And confirm by pressing" OK ".
  3. Proceed along HKEY_LOCAL_MACHINE \\ Software \\ Microsoft \\ WindowsNT \\ CurrentVersion \\ NetworkList \\ Profiles.
  4. Select unnecessary keys and delete.

Common mistakes

Often, the reason for the removal of the RPRO connection protrude frequent notes of errors arising at the time of connection. They are quite diverse:

  • 619 - issues when zero balance making an impossible connection.
  • 651 - occurs if does not respond The requested server.
  • 678 - Errors associated with incorrect parameters entered when setting up.
  • 691 - Notification of the error authentication of PPPOE or PPPOA, incorrectly entered data.
  • 734 - occurs when the connection completed the completion of the operation occurs.
  • 735 - Signals about incorrectly introduced IP address.
  • 800 - issues in the absence of a network connection.

This type of compound is far from being perfect, but it remains the most common and frequently used. If there is a good reason to get rid of it, it is not necessary to immediately delete, it will be enough to just turn it off, perhaps in the future he will still serve.

PPP stack technology ethernet networks It is relatively new, but has already received enough distribution. On the this moment It is determined by the RFC 2516 document, which was developed and released in February 1999. However, this document is not standard and is still informative. REDBACK NETWORKS, ROUTERWARE, UUNET, and OTHWORKS, ROUTERWARE, UUNET and OTHERWORKS. Thus, the "conscious age" of this technology is very small. Its use provides Internet service providers new opportunities in the organization and accounting user access to the network. This is especially true for those providers who plan or already offer their users access to the Internet using an Ethernet network, for example, in modern residential complexes, where the cable wiring twisted pair is no longer innovation.

It deserves special attention to the fact that to configure the provider's router, the hub installation in the entrance of a residential building, a network card and a small software to the user's computer does not need a modem, there is no need to occupy the only telephone line, since the service provider can now organize, restrict access and Accounting of user traffic in this way, as if the user works on the usual modem channel. Such an implementation has become possible thanks to the PPPoE technology, which launches the PPP session, but not over the modem connection, and on top of the Ethernet network.

At the same time, user authentication on PAP and CHAP protocols will be supported, dynamic selection IP addresses to users, destination of the address of the gateway, DNS server, etc.

PPPoE technology is at the moment it is one of the cheapest when providing users with access to Internet services in residential complexes based on Ethernet and using DSL technology.

Since the principle of work PPPoE is to establish a point-to-point connection over the total Ethernet environment, the process of functioning PPPoE must be divided into two stages. In the first stage, two devices must inform each other their addresses and set the initial connection, and in the second stage, launch the PPP session.

Stage of establishing a compound

Stage of establishing a connection between the client (user computer) and the server (provider access hub) is divided into several stages.

At the first stage, the client sends a broadcast query (destination address - Broadcast ADCOVERY INITIATION) to search for a server with PPPoE. This request will receive all network users, but only one will answer it who has PPPoE service support. Pado PPPOE Active Discovery Offer (PPPOE Active Discovery Offer) is sent in response to the Client, but if there are many PPPOE devices on the network, the client will receive many PADO packages. In this case, software The client selects the access concentrator you need and sends it a PADR PPPOE Active Discovery Request with information about the required service (the required service class depends on the service provider), the name of the provider, etc. After receiving the request, the access hub is prepared by the beginning of the PPP session and sends the PADS packet to the client (PPPOE Active Discovery Session-Confirmation). If all the services requested by the client are available (this package includes unique number Sessions assigned by a hub), then the second stage begins - the stage of the established session. If the services required by the client cannot be provided, the client receives the PADS package with an error in the service request.

Stage of the established session

The session begins using PPP packages. When establishing a PPP session, the user can be authenticated using RADIUS, and its traffic will be taken into account as in conventional modem access. He can assign dynamic IP address From the hub addresses pool, set the gateway and DNS server settings. At the same time, a virtual interface is appropriate at the access hub accordingly. It is desirable that the access hub send periodic queries to the client to determine its state. This operation is necessary to ensure that the client, which for any reason does not cut the session in the correct way, was not considered existing and the resources of the access hub was not repaid.

The completion of the PPPoE connection occurs at the initiative of the client or access hub using the PPPOE Active Discovery Terminate package.

The PPPOE protocol provides some additional functionsFor example, such as DOS attack protection (Denial of Service). Some DOS Types The attack is implemented by adding a special AC-Cookie Padi packets that allow access to limit the number of simultaneous PPPOE sessions to one client.

Testing products with PPPOE technology 01.04.01

Inline Technologies test laboratory has been tested different manufacturersUsing PPPoE technology. For this, the following equipment was used as access hubs:

  • Cisco 7206;
  • Cisco 3640;
  • Cisco 2620;
  • uS Robotics Total Control Access Concentrator.

Consider the configuration of the Cisco 2620 router to use the PPPoE service. The presented configuration was installed on our test router and worked together with the known software products customers. The inclusion scheme is shown in the figure, it corresponds to excerpts from the router configuration.

Many providers worldwide offer their Internet services through the so-called high-speed PPPoE connection (Point-to-Point Protocol Over Ethernet). To communicate with the Internet via PPPOE, providers usually give their clients a unique username and password that are necessary to connect to their networks.

The lack of PPPOE is to run the connection manually each time after the computer is turned on. This is an annoying inconvenience, which many users would like to forget once and forever. In this article, I will talk about the settings with which the computer with such a connection will be connected to the Internet automatically during startup.

1. Launch task scheduler

First of all, we need to launch a regular task scheduler. The simplest I. fast way Make it is to use the system search window. Enter the first few key request letters, and then click on the job scheduler element in the search results.

In Windows 10, the task scheduler can also be run from the Start menu: All applications \\ Administration ToolsWindows.

In the control panel, it is located on the next way: Control Panel \\ System and Security \\ Administration.

Regardless of the selected method, as a result, you will see this window:

2. Planning an automatic connection when entering the system

Now we need to schedule automatic connection to the Internet at each entrance to the system.

In the job scheduler window on the right click "Create simple task».

In the task creation wizard window, enter the name of the task, for example, Avtodozon. You can also enter a description, but it is not at all. Click "Next".

Next, you need to choose when our task should be performed specifically. Since our goal is that the PPPoE connection is automatically connected to the Internet each time you enter the system, select "when entering Windows". Click "Next".

The penultimate stage of creating a task is the choice of action. We need the PPPoe connection to start automatically with Windows. Accordingly, choose "Run the program". Click "Next".

And now the most important part of the process is to configure the script that will be automatically executed.

In order for the system automatically connected to the Internet via PPPoE, you must enter the following information:

  • In the program or script field, enter the command rasdial.
  • The "Add Arguments" field (optional) must contain the connection name (in quotes), as well as the username and password with a hyphen in front of them. For example, suppose your PPPoE connection is called Wwwand for connecting to it you use the username Ivan. and password 123456 . In this case, you must add the following arguments: " Www "Ivan 123456..

Field Work folder»Leave empty.

At the final stage you will see short description Created task. We click "Finish."

After closing the wizard, you will be returned to the main job scheduler window, where you will see that your task has been added to the list of other scheduled tasks.

3. Restart the computer and check

Finally, restart the computer to check the result of your actions. If all the steps were executed correctly, after rebooting the system should connect to the Internet automatically. Please note that from now on, each time the login log, the console window will appear on the screen, signaling the start of the connection process.

Excellent day!

Before you begin to configure the router, it is desirable to find out the necessary information. We need to find out what the Internet connection technology uses our Internet provider, you need to have the necessary parameters that will need to be specified in the router settings (depending on the connection technology). If, for example, the provider uses a dynamic IP connection to the technology, then you do not need any additional parameters. Enough, in the router settings, choose a dynamic IP, and the Internet will work.

Also, you need to know whether the provider makes a reference to the MAC address. If it does, then after connecting the cable to the router, the Internet will not work even after proper settingAfter all, the provider is not prescribed by the MAC address of the router.

Now we will understand everything in order.

The most important thing is to understand that the task of the router is connected to the Internet and distribute it to your devices. It establishes a connection with your provider just like a computer. In order to keep the router setting smoothly and without problems, you need to correctly specify the connection type (Wan Connection Type), and set the desired parameters.

What will happen if it is wrong to choose the connection type?

This is the most popular problem when setting up routers. The Internet will not work. Wireless network It will appear, but, after connecting to it, there will be no Internet on your internet devices. On computers, for example, there will be a connection status "without internet access". On the cable, from the router, the Internet will also not work.

Everything is clear here, the router did not set the connections with your provider, since the parameters are incorrectly specified.

How to find out the connection technology that my provider uses?

In Russia, Ukraine, and probably in other CIS countries, most often providers use such technologies: dynamic IP, static IP, PPPoE, PPTP, L2TP.

  • Dynamic IP. - The most normal technology :). A lot of Internet providers use it. Just connect the cable to the router and the Internet is already working, you do not need to customize anything. Just need to specify Dynamic IP technology. But, as a rule, in the router settings it is installed by default.
  • Static IP. - Not very popular technology. To configure such a connection on the router, you should know the IP address that you must issue the Internet Provider.
  • PPPoe - Popular technology (in Russia), which requires the creation of a special high-speed connection. If your provider works on PPPoE technology, then this connection was most likely created on the computer. In the router settings, you will need to select PPPoE, specify the login and password that the provider gives you. Also, you may need to set a static IP address.
  • PPTP. and L2TP. - Similar protocols, when setting up which you need to specify the name and login. As well as the server address and as needed - static IP. If the Internet was previously connected to a computer, then on the computer so de had a special connection you run.

I wrote a lot already, and I did not answer the main question.

Before you begin to configure the router, be sure to find out what technology your Internet provider uses.

How to find out? Call support for the provider and ask. Go to the provider's website and find the instructions for setting up the equipment. Or look in the documents you received when connected.

If you call support, then ask the provider to binding the MAC address, and what MTU value is better to specify in the router settings.

If you already know the connection technology, then you should also know the necessary parameters. If you have a dynamic IP, then as I have already written above, no parameters needed, but if you have a static IP, PPPoE, PPTP, or L2TP, then you need to know the login, password, static IP (if necessary), server address . Or only certain parameters (it all depends on the connection).

As a rule, this information is specified in the Internet connection contract.

Is there a binding to the MAC address?

Many providers, bind the Internet to the MAC address of a certain network device. Every computer network card, or a router, have a Mac address, and this address is prescribed from the provider.

If your Internet provider makes such a binding, then even after the proper adjustment of the router, the Internet will not work. Since most likely, the provider is registered the MAC address of your computer, not a router.

What to do in such a situation?

Find out if there is a binding on the MAC address. If not, then no additional settings Do not need. If there is a binding, then in the settings of the router, you need. It is necessary that on the router was the same Mac, as well as on the computer to which the Internet is tied. In the articles on setting up certain routers, I try to write how to do it.

There is one more option: View the router MAC address (as a rule, it is on the sticker on the router itself), call in support of the Internet provider, and tell them new MacTo which you need to tie the Internet.

Pledge of successful Wi-Fi router setup:

  • Correctly specify the connection type, and correctly set the necessary parameters (These are the settings on the "WAN", "Internet" tab, "Internet" - on different routers in different ways)who give out the Internet Provider.
  • Cloning the MAC address, or register the MAC address of the router if the provider makes binding.

These are two basic rules. Pay special attention to these two points, and you will succeed. The main thing is that the router will already distribute the Internet, and there to configure Wi-Fi NetworkInstall password, and other functions, you can already according to instructions for a specific manufacturer, or model. You can find these instructions on our website, or on the Internet.

(1500 bytes), which sometimes causes problems with poorly configured firewalls.

It is worth noting that some equipment Suppliers (Cisco and Juniper, for example) use the PPPoEoe term (PPPOE OVER Ethernet), meaning PPPoE that runs directly via Ethernet or other IEEE 802.3 networks, as well as PPPoE, working through Ethernet-related (Ethernet BridgeDeced Over) ATM, in order to distinguish from PPPoEOA (PPPOE OVER ATM), which runs on ATM Virtual Circuit to RFC 2684 and SNAP and encapsulate PPPOE. PPPoEOA is not the same as Point-to-Point Protocol Over ATM (PPPOA), since it does not use Snap.

PPPOE work is carried out in the following way. There is an Ethernet -Fer, that is, several connected network cards that are addressed by MAC addresses. Ethernet headers are containing the address of the sender of the frame, the address of the recipient of the frame and the frame type. One of the cards listens to the PPPoE server. The client sends a broadcast Ethernet frame to which the PPPoe server must reply (the address sender's address is its MAC address, frame recipient address - FF: FF: FF: FF: FF: FF and frame type - PPPoe Active Discovery Initiation). PPPoE server sends a call to the client (the sender address of the frame is its MAC address, the address of the recipient of the frame - the client's MAC address and the type of frame - PPPoe Active Discovery Offer). If there are several PPPOE servers on the network, then they all send the answer. The client selects the appropriate server and sends him a connection request. The server sends a confirmation to the client with a unique session identifier, all subsequent frames in the session will have this identifier. Thus, a virtual channel is created between the server and the client, which is identified by the session identifier and the client MAC addresses and the server. Then the PPP connection is installed in this channel, and already in PPP packets are packaged.

PPPoE Discovery (PPPOED)

Padi.

Padi. - PPPOE Active Discovery Initiation.

If the user wants to connect to the DSL Internet, first its machine must detect the access hub on the provider side (Point of Presence (POP)). Interaction through Ethernet is possible only through MAC addresses. If the computer does not know the DSL-AC MAC address, it sends a PADI package via Ethernet Broadcast (Mac: FF: FF: FF: FF: FF: FF) This PADI package contains the MAC-address sent by its machine.

An example of a Padi Package:

Frame 1 (44 bytes on Wire, 44 bytes Captured) Ethernet II, SRC: 00: 50: DA: 42: D7: DF, DST: FF: FF: FF: FF: FF: FF PPP-Over-Ethernet Discovery Version: 1 Type 1 Code Active Discovery Initiation Session ID: 0000 Payload Length: 24 PPPOE Tags Tag: Service-name Tag: Host-Uniq Binary Data: (16 bytes)

Src. (\u003d Source) represents the MAC address of the machine sent Padi.
DST. (\u003d Destination) is a broadcast Ethernet address.
The PADI package can be obtained by more than one DSL-AC.

Pado.

Pado. - PPPOE Active Discovery Offer.

As soon as the custom machine sent a PADI package, DSL-AC responds by sending a PADO-package using MAC addresses that come with PADI. The PADO packet contains DSL-AC MAC addresses, their names (for example, LeiX11-ERX \u200b\u200bfor the T-COM DSL-AC concentrator in Leipzig) and the name of the service. If more than one DSL-AC point responded with a PADO packet, a custom machine selects a DSL-AC specific POP using the names or service names.

An example of a PADO-package:

Frame 2 (60 bytes on Wire, 60 bytes Captured) Ethernet II, SRC: 00: 0E: 40: 7B: F3: 8A, DST: 00: 50: DA: 42: D7: DF PPP-Over-Ethernet Discovery Version: 1 type 1 Code Active Discovery Offer Session ID: 0000 Payload Length: 36 PPPoe Tags Tag: Service-Name Tag: AC-Name String Data: IPZBROOL TAG: Host-Uniq Binary Data: (16 bytes)

AC-NAME - String Data Represents a string AC name, in this case "IPZBR001" (Arcor DSL-AC in Leipzig).
Src. Represents the DSL-AC MAC address.
The DSL-AC MAC address also identifies the DSL-AC manufacturer (in this case, Nortel Networks).

Padr.

Padr. Deciphered as PPPoE Active Discovery Request.

As stated above, the user machine must select POP (access point) - this is done using the PADR packet, which is sent to the MAC address of the selected DSL-AC.

Pads.

Pads. - PPPOE Active Discovery Session-Confirmation.

The PADR packet is confirmed by the Pads Package shipping concentrator, session id comes in it. A DSL-AC connection for this access point is now fully installed.

Padt.

Padt. - PPPoE Active Discovery Termination.

This package breaks off the POP connection. It can be sent either by the user or by the DSL-AC.

The advantages of the scheme

  • IP headlines in the Ethernet environment is ignored. That is, the user can assign the IP address of its network cardBut this will not lead to the "collaboration" of the network (theoretically, when working with a network hub, "collapse" should not occur and when changing the user MAC address even to the server address, and when working with a network switch, it all depends on the switch design).
  • Each connection is separated from others (it works in its channel).
  • Settings (IP address, gateway address, DNS address servers addresses) can be transmitted by the server.
  • PPP connection is easily authenticated and is checked (for example, with RADIUS).
  • PPP connection can be encrypted. For example, when working with a network hub (when all Ethernet traffic can be seen on each network card), you can read someone else's IP traffic is very difficult.

Notes

Links

  • RFC 2516 - A Method for Transmitting PPP Over Ethernet (PPPOE)
  • RFC 3817 - Layer 2 Tunneling Protocol (L2TP) Active Discovery Relay for PPP Over Ethernet (PPPOE)
  • RFC 4638 - Accommodating A Maximum Transit Unit / Maximum Receive Unit (MTU / MRU) Greater Than 1492 in the Point-to-Point Protocol Over Ethernet (PPPOE)

see also