all 3 comments

[–]zanfarCCENT 0 points1 point  (2 children)

Your question isn't really clear, and you provide no context for your quote, so we don't have any idea what you are really asking. This is probably why you haven't received any responses yet.

I've never heard of "Cisco Bordless Networks" especially at the CCNA level, nor have I heard about "aggregating L2 domains" in the context of "L3 boundaries". Please elaborate, provide a description of what you are trying to solve, or page and book title if this is a quote.

[–]jeff597[S] 0 points1 point  (1 child)

Sorry. It's about Cisco BORDERLESS Networks. It can be found in CCNA routing and switching essentials under the following path:

Chapter 4 Switched Networks 4.1 LAN Design 4.1.1 Converged Networks Cisco Borderless Networks

I quoted directly from the course material :

Distribution Layer

The distribution layer interfaces between the access layer and the core layer to provide many important functions, including: ... *Aggregating Layer 2 broadcast domains and Layer 3 routing boundaries. ...

[–]zanfarCCENT 0 points1 point  (0 children)

In that case, I think they mean that the Distribution layer serves primarily as the L2/L3 boundary, and aggregates all the below VLANs. The "Layer 3 routing boundaries" statement is confusing as we don't generally think of VLANs as L3 boundaries, but they are that as well (as subnets).