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Original Disclosure Date: March 15, 1999 Update to Network Disclosure News # 433 dated April 27, 2001
Summary:	This disclosure announces the cancellation of the Qwest Modem Aggregation Service (MAS) effective May 1, 2001. Qwest will no longer make this service available to new customers or allow additions to existing customer's service. Existing service will be "grandfathered." Previously this disclosure announced the availability of the Layer Two Tunneling Protocol (L2TP) interface, User Datagram Protocol (UDP) and IP Protocol in addition to the currently disclosed Frame Relay (Network Disclosure Announcement No. #401) and (ATM) Asynchronous Transfer Mode (Network Disclosure Announcement No. #400) cell relay user network interface (UNI). These interfaces were used in conjunction with the Qwest "Modem Aggregation Service (MAS)." They were the interfaces provided to a Frame Relay or ATM end user who desired to connect to MAS. For both Frame Relay and ATM customer network interfaces, the customer CPE must support an L2TP Tunnel Interface, UDP: User Datagram Protocol Specifications and IP Protocol.
Locations and Timing of Deployment:	Locations where MAS is planned or currently available can be found in Attachment 1. In addition, any new deployment locations will be added to the Qwest Web site at http://www.qwest.com/disclosures in disclosure #433.
Pricing:	The Qwest MAS Service using the L2TP interface was offered under tariff in the locations identified in Attachment 1 (see "Locations" above).
Interface Requirements:	MAS Frame Relay Customer Network Interface: At the Layer 1 (Physical Layer) level, the MAS Frame Relay Customer Network Interface consists of the following protocol: At the physical layer, MAS supports all Frame Relay UNI Access Links (including 56 Kbps 4-wire, 64 Kbps 4-wire, 128 Kbps 2-wire, 1.544 Mbps (DS1), Fractional DS1, or 44.736 Mbps(DS3)) as defined in the Qwest Frame Relay Service Network Disclosure Announcement No. 401 at Web location http://www.qwest.com/disclosures For MAS service, one Frame Relay PVC is supported at the Customer Network Interface. On behalf of the MAS customer, the Frame Relay PVC carries all dial-in traffic for all end users within a calling area. The PVC originates within the MAS network. MAS ATM Customer Network Interface: At the Layer 1 (Physical Layer) level, the MAS ATM Customer Network Interface consists of the following: All ATM-CRS UNI Access Links (including DS1, DS3, or OC3) as defined in the Qwest ATM Cell Relay Service Network Disclosure Announcement No. 400 at web location http://www.qwest.com/disclosures For MAS service, one ATM CRS Permanent Virtual Circuit (PVC) is supported at the Customer Network Interface. MAS uses the ATM UBR (Unspecified Bit Rate) Class of Service on the PVC. On behalf of the MAS customer, the ATM PVC carries all dial-in traffic for all end users within a calling area. The PVC originates within the MAS network (RAS network element). MAS Layer 2 Option: IP Encapsulation Over Frame Relay For MAS Layer 2 Frame Relay service interoperability, the customer CPE (LNS) must also conform to the following IETF standard IETF STD55 (RFC 2427), "Multiprotocol Interconnect Over Frame Relay". The following sections of this standard apply to MAS-CPE interoperability: Section 3 Frame Format; Section 4.1 Routed Frames Ð Format of Routed IP Datagram (NLPID 0xCC); Section 6 Fragmentation; Section 8 IP over Frame Relay (both NLPID value indicating IP = 0xCC and NLPID value indicating SNAP where PID = 0x0800 (IP). All other sections do not apply to MAS-CPE interoperability. MAS Layer 2 Option: IP Encapsulation over ATM For MAS Layer 2 ATM service interoperability, the customer CPE (LNS) must also conform to the following IETF Standard: IETF RFC 2684, "Multiprotocol Encapsulation over ATM Adaptation Layer 5.", July 1993, Payload Format for Routed IP PDUs with OUI value 0x00-00-00 (PID = Ether Type) and Ether Type = 0x08-00 (IP PDU) (as specified in Section 3 AAL5 Frame Format and Section 4.1 LLC Encapsulation for Routed Protocols). All other sections of this standard do not apply to MAS-CPE interoperability. MAS Layer 3 Interface: IP For both MAS Frame Relay and MAS ATM customer network interfaces, the customer CPE must support the IP Version 4 protocol as specified in IETF STD0005 (RFC 791), "IP: Internet Protocol." The CPE must support the entire specification to be interoperable with MAS. MAS Layer 4 Interface: L2TP Tunnel Type: For both Frame Relay and ATM customer network interfaces, the customer CPE must support an L2TP Tunnel Interface. The L2TP tunnels originate within the MAS network. The customer CPE (LNS) must support dynamic creation of multiple tunnels. CPE support for at least 8 tunnels per calling area is recommended to assure operation in any location where MAS is available. Smaller calling areas will need fewer tunnels than larger calling areas. The Qwest MAS network elements initiate, within the network, L2TP-UDP formatted frames. The customer CPE (LNS) must support L2TP authentication as specified in section 5.1.1 of the L2TP specification. For L2TP Tunnel Type MAS interoperability, the following IETF standards must be supported by the customer CPE (LNS): User Datagram Protocol and L2TP Protocol. See Technical Publication 77402 "Modem Aggregation Service" Issue B dated April 2000 for more information. User Datagram Protocol For MAS interoperability, the CPE must support the IETF User Datagram Protocol (RFC 768) standard. L2TP Protocol To be interoperable with MAS, the CPE must support the following L2TP specifications: Dynamic L2TP tunnel establishment from L2TP tunnels that originate within the MAS network. The tunnels do not originate from the dial-in user premise equipment. Have capacity to support the establishment of at least 8 tunnels per calling area served by the LNS. L2TP tunnel authentication with a "shared secret" that is made available with the MAS subscription. This "secret" is only known to the MAS customer and the Qwest MAS Customer Service Center. L2TP session establishment and encapsulation of multiple concurrent PPP user data streams. For each user call accepted there is a corresponding L2TP session establish. L2TP Tunneling Protocol (IETF RFC 2661) standard compatible as qualified below: Section 2.0. The network between MAS and the LNS is Frame Relay or ATM. Section 4.3. Hiding of AVP Attribute Values. This section describes a method of indicating to a peer that the present value of an attribute value pair is hidden. MAS does not support the hiding of values of AVPs currently. Section 4.4.5. Proxy LCP and Authentication AVPs. This section describes Attribute Value Pairs (AVP) and methods for negotiating LCP and user authentication. MAS does partial LCP negotiations and forwards the result to the LNS. MAS does not forward the authentication (PAP or CHAP) to the LNS. The authentication is discarded, which causes the client to re-negotiate authentication with the customer LNS. There are no known incompatibilities with this method, as PPP is structured to re-negotiate this automatically. Note: This is not a consideration for compulsory tunneling based on Called or Calling Station ID. Section 5.2.2 Outgoing Call Establishment. MAS does not support Outgoing Call Establishment. Section 5.4 Using Sequence Numbers on the Data Channel. This section describes a method for enabling and disabling sequence numbers for the data channel. Sequence numbers are defined in the L2TP header for control messages and optionally for data messages (see Section 3.1). These are used to provide a reliable control message transport (see Section 5.4) and optional data message sequencing. MAS sends payload with sequence numbers, however, it will accept payload with or without sequence numbers. Acronym Key ATM Asynchronous Transfer Mode BRI ISDN Basic Rate Interface CPE Customer Premise Equipment CRS Cell Relay Serivce FR Frame Relay IETF Internet Engineering Task Force IMT Inter- Machine Trunk IP Internet Protocol, RFC 791 ISDN Integrated Services Digital Network ISP Internet Service Provider LAC L2TP Access Concentrator L2TP IETF Layer 2 Tunneling Protocol LNS L2TP Network Server MAS Qwest Modem Aggregation Service PPP Point to Point Protocol, RFC 1661 PRI ISDN Primary Rate Interface PSTN Public Switched Telephone Network PVC Permanent Virtual Circuit RAS Remote Access Server RFC Request For Comment TA ISDN Terminal Adapter UDP User Datagram Protocol, RFC 768 UNI User Network Interface
Additional Information:	All IETF standards identified herein can be found at web location http://www.rfc-editor.org/rfc.html The draft L2TP standard can be found at web location http://www.ietf.org/ Any customer premises equipment vendor/manufacturer or enhanced services provider wanting to offer products or services in conjunction with the MAS Interfaces may request additional information by contacting: Susan Davey !NTERPRISE Product Management Qwest Communications 1999 Broadway, 5th Floor Denver, Colorado 80202 (303) 308-5062
MAS is available in the following local calling areas. Specific Central Offices are identified in the Qwest Tariffs located at the following WEB site: http://tariffs.uswest.com:8000/. This list is subject to change. * An asterisk in the margin denotes a change or addition to the previous release. Free Calling Area State Locations Can be Found in the Tariffs Below Availability Date Phoenix AZ Arizona Exchange and Network Services Tariff and Price List Ð 5. EXCHANGE SERVICES 5.1 EXCHANGE AREAS 04/10/00 Denver CO Colorado Exchange and Network Services Tariff and Price List Ð 5. EXCHANGE SERVICES 5.1 EXCHANGE AREAS 04/10/00 Minneapolis St. Paul MN Minnesota Exchange andNetwork Services Tariff Ð 5. EXCHANGE SERVICES 5.1 EXCHANGE AREAS 04/10/00 Portland OR Oregon Exchange and Network Services Tariff Ð 5. EXCHANGE SERVICES 5.1 EXCHANGE AREAS 04/10/00 Salt Lake City UT Utah Exchange and Network Services Tariff Ð 5. EXCHANGE SERVICES 5.1 EXCHANGE AREAS 04/10/00 Bremerton Seattle Silverdale Tacoma WA Washington Exchange and Network Services Tariff Ð 5. EXCHANGE SERVICES 5.1 EXCHANGE AREAS 04/10/00
NOTE: This announcement has been released in accordance with the FCC Rule 51.333(a), Certification of Short Term Public Notice.

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