We know your network. But we also know your name Extended Native LAN

We know your network. But we also know your name Extended Native LAN Product Overview

What is ENLAN? ENLAN is an extension of the NLAN connectivity between two or more TWTC markets across the TWTC IP Backbone. Speeds from 2M to 1G. Only one instance of ENLAN per market is required. Each of the markets may have more than one location. Local “access” to the locations in each market are purchased via the normal SNLAN product. Connecting via Elite NLAN is NOT an option. 2

Why ENLAN? NLAN is a metro solution Many of our customers are multi-market TWTC has a powerful IP Infrastructure to support customer multi-market needs 3

ENLAN Reach is SAME as IP Reach 4

Basic Uplink Architecture The customer’s VLAN in one city is mapped to an MPLS tunnel at the Edge Router. IP Backbone IP Core Routers Juniper M480 M960 etc 1 and 10G Uplinks MPLS IP Edge Router Ethernet / VLAN 1 and 10G Uplinks Metro Switch Cisco 7609 Edge Switch: Cisco 3xxx, 49xx, etc 5 Metro Ethernet Ring

What is an MPLS tunnel? Multi-Protocol Label Switching creates a label switched path similar to a virtual circuit. It is similar to the MEF term of an EVC. Also similar to VCs in Frame Relay or ATM in that is sets a pre-determined “path” through the network for customer traffic. ENLAN over MPLS is a best effort service unless CoS is purchased. Our customer’s NLAN traffic is mapped to a specific MPLS tunnel or path based on the destination desired; logical separation is still maintained to provide the same level of “security” that is found in FR or ATM networks. 6

End-to-End Architecture TWTC IP Backbone L2 VPN Tunnel Cisco 7609 Cisco 7609 Cisco 3400 Cisco 3400 Customer Premise EXAMPLE of two customer sites connected by ENLAN CPE CPE City A 7 Customer Premise City Z

“Point-to-Point” ENLAN Example 8

Multipoint ENLAN ENLAN product is built differently as a multipoint or “full mesh” product, as opposed to only connecting two markets. MP ENLAN connection extends between the IP POPs from three or more TWTC Cities. Local Ethernet connectivity, via the SNLAN product, is still required to connect the customer locations in each city to the IP POP in each city. Multipoint ENLAN not priced differently than p2p, but is important to distinguish at the time of SOF/OE. Changing from two markets (p2p) to 3 or more is briefly service impacting to the customer due to config. changes. 9

Multi-point ENLAN Example 10

End-to-End Architecture: MP Cisco 7609 nnel Cisco 7609 TWTC IP Backbone L2 V P N Tu L2 VPN Tunnel L N Tu 2 VP Cisco 3400 CPE City B n ne l Cisco 7609 EXAMPLE of three customer sites connected by ENLAN Cisco 3400 CPE City A 11 CPE City C Cisco 3400

Multi-point Technical Implementation Uses VPLS to make backbone appear as a switch to all sites for each customer. VPLS is a networking approach enabled at the edge router, or “HAGG,” which extends the customer’s Ethernet LAN between multiple NLAN’s. From the high speed aggregation router (HAGG), the ENLAN traffic will be sent though the backbone using VPLS to the HAGG on the destination NLAN site. BGP is used to build the IP/MPLS LSP mesh when 3 or more markets are requested . The edge router acts as a layer 2 learning switch building a MAC table to determine which LSP to send a frame over. 12

Customer Uses for ENLAN The ENLAN applications mirror those for existing SNLAN customers. Applications include typical bulk file transfers (e.g. Imaging, CAD/CAM, data repository transfers), private intranet, LAN/email, remote office connectivity into the HQ, etc. Default/Basic service is not a dedicated bandwidth technology and should never be sold as such; it mirrors a best effort “virtual circuit” environment. Premium Class of Service available on ENLAN if the metro SNLAN is also enabled for CoS. Flat fee for CoS allows most all marked traffic to flow between markets. 13

VLAN Tagging Individual tags or unlimited tags should be ordered in the NLAN product suite. ITS is NOT SUPPORTED on the ENLAN product beyond a single tag: the single tag is equivalent to UTS in that it still only consumes a single S-Tag. ENLAN CANNOT be used in conjunction with the Wholesale SNLAN product because of VLAN tagging issues. 14

Additional ENLAN Notes ENLAN may be used to connect adjacent cities; the price may be waived but the technology and VLAN tag limits per prior slides remains in place. ENLAN cannot exceed 1G of bandwidth. E-Line should always be considered over ENLAN when the service request is point to point only and the city pairs match the Nationl Ethernet footprint. Customer can “manage” traffic into and out of a market and limit the size of the ENLAN instance per market to whatever they want. When connecting a market that has more than one metro location, it does not make any difference which address you associate the ENLAn instance with. 15