7 MExE bearer requirements

02.573GPPMobile Station Application Execution Environment (MExE) Service description Stage 1TS

The MExE execution environment is isolated from the network specific bearers by the transport protocol. This clause addresses the basic requirements for bearer services which are of fundamental importance and dictate the type of service offered to the MExE transport protocol.

The characteristics of some existing different bearer services are presented in Table 1, and the emergence of additional bearers is foreseen with the evolution of UMTS.

Table 1: Characteristics of bearer services

Bearer

Category

Example

Channel

Bitrate
(bit/s)

Latency
(ms)

Layer 3 Message max. length
(octets)
see note

Message delivery

Endpoint (MS-?)

Concurrency with CS-call

Example usage

SMS

(PTP)

SDCCH

SACCH

660

150

240

480

140

store and forward

SMSC

yes

messaging services

SMSCB

CBCH

44

N/A

83

broadcast

BSC

Message-based

(connectionless)

GPRS

PDCH

nx8000

20

1500

SGSN

dependent on mobile and network capabilities

Internet

WWW

access

Message-based
(connection oriented)

USSD

SDCCH
FACCH

660
1100

240
120

160

direct

MSC, VLR, HLR or other PLMN node

yes

TeleVAS

UUS

128 (32)

other MS

CNAP

Circuit-based
(connection oriented)

HSCSD

TCH

n9600
n14400

N/A

N/A

N/A

other end

no

FTP

NOTE: that the indicated message lengths do not reflect the capability for concatenation or compression of messages for specific bearers

The user is not expected to access the bearer directly, but to do so via a MExE transport API. All bearers may not be available in all implementations.

The MExE transport protocol shall have access to a range of bearer services, including support of telecom-related services and data-related services. Telecom-related services are carried out between the MExE MS and the MSC, VLR, HLR, SCP or other operator-managed GSM/UMTS nodes in the network. Data-related services are mainly carried out between the MExE MS and an interworking function or a gateway node to external networks.

Some applications require a bearer which can operate both without an ongoing call (stand-alone) and in parallel with a circuit switched call, whereas other applications do not require bearer operation in parallel with a circuit switched call. The MExE transport protocol shall have access to both types of bearers.

In order to support a wide variety of applications, the MExE transport protocol shall have access to both connection-oriented and connectionless bearers. Likewise, both message-based and circuit-based bearers shall be available.

The integrity of the bearers must be assured to ensure their capability to correctly and properly transfer applications and applets between the MExE service provider and the MExE MS.