Chapter 4 of 7 · MikroTik MTCUME

Bridging

Joining LANs over L2TP with EoIP, VPLS or BCP, plus the Multilink Protocol and MLPPP link bundling on RouterOS.

  • 4topics
  • 17 minfast track
Start with L2TP and EoIP Bridging

Topics in this chapter

Take them in order, or jump to the one you need.

  1. 1L2TP and EoIP BridgingJoin two remote LANs at Layer 2 with an EoIP tunnel over L2TP: tunnel id, endpoint addresses, bridge ports, IPsec protection and…4 min
  2. 2L2TP and VPLS BridgingLearn how a VPLS pseudowire bridges two LANs over MPLS and LDP on RouterOS, why a loopback and tunnel path are needed, and how to…4 min
  3. 3L2TP and BCP BridgingBridge two LANs over an L2TP tunnel with the Bridge Control Protocol: set the bridge in the PPP profile on both ends, add MRRU…4 min
  4. 4Multilink Protocol and MLPPPLearn how the PPP Multilink Protocol and MRRU work on RouterOS, how MLPPP bundles PPPoE links into one interface, and what must…5 min

About this chapter

What this chapter covers

This chapter shows how to join remote LANs at Layer 2 across a tunnel, and how to bundle PPP links together.

Bridging over a tunnel makes two sites behave like one Ethernet segment. Hosts at both ends can share a subnet, a gateway and a DHCP server. RouterOS gives you three ways to do this, and each has its own strengths.

The chapter ends with the Multilink Protocol, which fragments PPP packets and lets you bundle several links into one.

How the topics fit together

The three bridging methods solve the same problem in different ways, and multilink supports them.

L2TP tunnelIP path between sitescarriesEoIPseparate tunnelorVPLSMPLS pseudowireorBCPbridge in the PPP session

The pages compare the methods one by one:

  • EoIP runs an Ethernet tunnel inside the L2TP tunnel. It is simple, but it is MikroTik specific.
  • VPLS uses MPLS labels and LDP. It takes more setup, but it is a standard that other vendors support.
  • BCP puts the bridge setting into the PPP profile, so the tunnel itself carries Ethernet. It needs no second tunnel.
  • Multilink and MLPPP turn on fragmentation with MRRU, and bundle several links into one logical interface.

MRRU appears twice. BCP needs it so that full sized Ethernet frames fit, and MLPPP needs it to bundle links.

Note

Every method gives you one broadcast domain across two sites, so loops are a real risk. Keep a single path or enable spanning tree.

How to use these pages

Each topic page has the same shape, so you can skim for what you need.

  • What it is: the idea in plain words.
  • How it works: the mechanism, with diagrams and example commands.
  • What to remember for the exam: the facts to memorise.
  • Common mistakes: the classic traps.
  • Check yourself: three questions to test your understanding.

Start with the L2TP page from the earlier chapter, because every bridging method here sits on top of that tunnel. Build one method at a time in a two router lab. After each one, check the bridge host table to see MAC addresses from the far site.

Pay attention to the comparison tables. A common exam question asks which method fits a described situation.

Ready for more practice?

The full MikroTik MTCUME question bank has 482 questions, with timed practice exams and an explanation for every answer.

SubscribeTry Sample Exam

This study guide is independent and is not affiliated with, endorsed by, or sponsored by MikroTik. Vendor names, certification names and exam codes are trademarks of their respective owners and are used for identification only.