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What is the difference between Targeted LDP and Directed LDP in MPLS?

Directed LDP is not a term that appears in the LDP specification (RFC 5036.) Perhaps you're trying to understand the difference between Basic Discovery which uses LDP Link Hellos and Extended ...
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3 votes
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How are labels in LDP "Label Mapping Message" associated with IP prefix?

FEC Elements are addresses or prefixes which, when included in an FEC TLV as part of a Mapping Message, are mapped to the associated label. If you expand the FEC Element 1 section of your packet ...
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3 votes

Why VPWS service - MPLS has a two ethernet frame headers?

Why there is a need for again source MAC and destination MAC addresses? The original source and destination MAC addresses have no meaning while the packet is in the tunnel. My understanding is ...
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3 votes

VPLS Multihoming on Junos - FEC confusion‏

Part of it comes down to what's supported, you might have PE's running older code that don't support FEC129. FEC128 multihoming was introduced in Junos 7.5 (see here). FEC129 multihoming was ...
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3 votes

IGP vs LDP forwarding

Welcome to Network Engineering! LDP is not a routing protocol, so Administrative Distance does not apply. It's not clear from your question, but how the router forwards depends on what kind of packet ...
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3 votes

Do Juniper l2circuit services (ccc) support a mismatched encapsulation type?

Juniper does support mismatched encapsulations, but that technically isn't needed for what you're trying to accomplish. To be frank, Juniper's terminology for the different encapsulation types and how ...
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LDP: which FEC an egress router has to advertise when using Ordered Control?

Which FEC an egress router has to advertise when using Ordered Control? ... is it expected to announce one single FEC for each of those in its MPLS-Domain or to announce one label for each of those ...
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LDP: which FEC to advertise when using Ordered Control?

Depends on what you mean by a destination. In IPv4 world, FEC is actually an IPv4 prefix (or a route in other words). Simply put a router will map each prefix it learns via IGP to a label. RFC 3036 ...
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2 votes

H-VPLS application with different types of VPLS

@Radovan. Refernece to your question "Is H-VPLS applicable for every type of VPLS network? (any other than LDP-based VPLS as in RFC 4762)" , I think H-VPLS was a fix to lessen extensive LDP peering ...
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Do Juniper l2circuit services (ccc) support a mismatched encapsulation type?

EDIT: Keeping the original answer here to document that some of Juniper's docs appear to conflict with Jordan's expertise on l2circuit configurations. See his answer for more details... Question: ...
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2 votes
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What are LDP-MPLS advantages?

In todays routers routing lookup is done in hardware, usually in TCAM, which is as fast as ILM lookup. So no advantage in lookup speed. So why is it even needed? For tunneling. If you want to deploy a ...
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2 votes

MPLS LDP transport address should it be always loopback IP

Since the LDP is running using TCP, it needs to establish session with every LDP speaking neighbor. Sometimes those neighbors are one hop away and you can use the point-to-point addresses configured ...
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2 votes
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Does LDP not generate a label for default route for ISIS Level 2?

Some implementations set the ATT bit automatically and provide you a command or knob under a configuration stanza to disable it. i.e on Juniper: ignore-attached-bit Ignore the attached bit on IS-IS ...
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2 votes

Why VPWS service - MPLS has a two ethernet frame headers?

VPWS is a point to point L2VPN, using this technology two geographically remote hosts from the same IP subnet are able to communicate as if they were connected to the same switch. This thing is ...
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2 votes
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Why are the LDP installed LSPs not seen in the output of "show mpls lsp" in Junos?

Does the show mpls lsp in Junos show only static and RSVP LSPs? Or am I missing something here? It's counter intuitive, but you're correct, only RSVP LSPs are shown with show mpls lsp. It's ...
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1 vote

PE route down in LDP based VPLS Connection in Juniper MX

The VC will go down if the interface (in your case ge-2/1/5 goes down), so run show interfaces ge-2/1/5 and confirm the Last Flapped: time against your log entries.
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1 vote

VPLS Multihoming on Junos - FEC confusion‏

I'm not sure that FEC128 is limited to just manual discovery of PWs. I've always used the FEC128 multi-home method described in the link with BGP auto-discovery and it works just fine - if I ...
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