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UPDF Example

Tunnel SS7 via Ethernet

In the following example, the objective is to tunnel SS7 signaling information from one Signaling Point to another via Ethernet. SIP envelops all SS7 ISUP messages in MIME encoded SDP.

The CSP can handle this scenario because it supports traditional PSTN protocols and VoIP protocols such as SIP.

Figure 7-1 Network for Example

In this network, you can configure SS7 channels on the CSP to report incoming SS7 ISUP calls to either:

• Report an Request for Service message to the host

• Perform Layer 4 routing to the SIP channels

In either case, you should configure the NPDI Interworking on the SS7 channels on the CSP #1. This way, if a call is reported to the host, the RFS will have UPDF TLVs.

If the host is required to route the call to the SIP side, the host needs to:

• Examine the Request for Service message and determine that it is an SS7 ISUP call.

• Issue a Route Control message that will have all pertinent UPDF TLVs related to SS7 ISUP parameters so that all those TLVs can carry MIME encoded DSP in the Invite message

Sample RFS for Incoming Call

The following sample Request for Service message for an incoming call assumes NPDI Interworking is enabled on SS7 channels.

00 5f 00 2d 00 01 01 00 01 0d 03 00 04 01 01 33 01 03 00 33

00 4b 00 08 27 4e 00 02 00 05 27 25 00 02 21 00 27 46

00 01 02 27 17 00 08 01 01 0a 86 25 00 00 12 27 18 00

0a 01 10 81 0a 0a 31 35 55 12 12 27 7d 00 07 00 01 00

06 00 01 00 27 61 00 08 00 00 00 04 01 00 00 00 27 7e

00 03 01 02 02

Sample Invite Message

The host needs to issue a Route Control message that embeds all of the TLVs required for this RFS. The UPDF tunneled Invite message goes out to the other CSP.

The corresponding Invite message appears as follows:

1 -SENT To 135.119.55.45:5060 at 3557

INVITE sip:8625000012@135.119.55.45:5060 SIP/2.0

Via: SIP/2.0/UDP 135.119.55.42

To: 8625000012<sip:8625000012@135.119.55.45:5060>

From: 3135551212<sip:3135551212@135.119.55.42:5060>;tag=17452195de5

Call-ID: EXCEL-CSP1.6d1.3557.120@135.119.55.42

Contact: 3135551212<sip:3135551212@135.119.55.42:5060>

User-Agent: Excel/82.0.10

Supported: timer

Session-Expires: 1800

Min-SE: 300

CSeq: 1 INVITE

Content-Type: Application/Multipart

Content-Length: 482

Content-Type: multipart/mixed; boundary="de5=_78=_e5d"

--"de5=_78=_e5d"

Content-Type: application/sdp

v=0

o=sip 14999 14999 IN IP4 135.119.55.42

s=SIP_Call

c=IN IP4 135.119.55.48

t=0 0

m=audio 14980 RTP/AVP 18

a=rtpmap:18 G729/8000

--"de5=_78=_e5d"

Content-Type: application/SS7 ISUP; version:EXCEL-UPDF

Content-Transfer-Encoding: binary

03 00 33 00 67 00 0c 27 4e 00 02 00 05 27 25 00 02 21 00 27

46 00 01 02 27 17 00 08 01 01 0a 86 25 00 00 12 27 18 00 0a

01 10 81 0a 0a 31 35 55 12 12 27 7d 00 07 00 01 00 06 00 01

00 27 61 00 08 00 00 00 04 01 00 00 00 27 92 00 04 87 77 37

30 27 93 00 04 00 00 3a 84 27 b0 00 02 01 12 27 b1 00 02 01

02 27 7e 00 03 08 00 00

--"de5=_78=_e5d"--

See Signaling System Number Seven.
The protocol used in most local area PC networks. Typically, most Ethernet networks support data transmission speeds up to 10 Mbps, but 100 Mbps is also possible.
Session-Initiation Protocol. A signaling protocol used for establishing sessions in an IP network. A session could be a simple, two-way telephone call, or it could be a collaborative multi-media conference session.
See Integrated Services Digital Network User Part.
Public Switched Telephone Network
Voice over Internet Protocol. The delivery of voice information in digital form in discrete packets rather than in the traditional circuit-committed protocols of the public-switched telephone network (PSTN).
Call processing layer of the CSP.
Network Protocol Data Intelligence. Also called “Interworking,” it is a software product that operates within Excel’s Call Control (Layer 4) and Services (Layer 5) call processing layers. NPDI is meant to enhance Excel’s call processing product offering by allowing call processing layers (specifically Layers 4 and 5) to perform advanced analysis, generation, and conversion of Network Signaling (NS) Layer 3 information.
Interworking is a software feature within the Excel platform call control layer that enables protocol conversion by analyzing and converting Network Signaling (NS) Layer 3 information.
See Request For Service.
See Universal Protocol Data Format.
Digital Signal Processor
Real-Time Transport Protocol. Supports transport of real-time data like interactive voice and video over packet-switched networks.