01: /*
02: * BandWidth.java
03: *
04: * Created on December 18, 2001, 3:59 PM
05: */
06:
07: package javax.sdp;
08:
09: /** A Bandwidth represents the b= fields contained within either a MediaDescription or a
10: * SessionDescription.
11: *
12: * This specifies the proposed bandwidth to be used by the session or media, and is optional. Multiple
13: * bandwidth specifiers of different types may be associated with the same SessionDescription. Each
14: * consists of a token type and an integer value measuring bandwidth in kilobits per second.
15: *
16: * RFC 2327 defines two bandwidth types (or modifiers):
17: *
18: * CT
19: * Conference Total: An implicit maximum bandwidth is associated with each TTL on the Mbone or
20: * within a particular multicast administrative scope region (the Mbone bandwidth vs. TTL limits are given
21: * in the MBone FAQ). If the bandwidth of a session or media in a session is different from the
22: * bandwidth implicit from the scope, a 'b=CT:...' line should be supplied for the session giving the
23: * proposed upper limit to the bandwidth used. The primary purpose of this is to give an approximate
24: * idea as to whether two or more conferences can co-exist simultaneously.
25: * AS
26: * Application-Specific Maximum: The bandwidth is interpreted to be application-specific, i.e., will be the
27: * application's concept of maximum bandwidth. Normally this will coincide with what is set on the
28: * application's "maximum bandwidth" control if applicable.
29: *
30: * Note that CT gives a total bandwidth figure for all the media at all sites. AS gives a bandwidth figure for a
31: * single media at a single site, although there may be many sites sending simultaneously.
32: *
33: * Please refer to IETF RFC 2327 for a description of SDP.
34: *
35: *
36: * @author deruelle
37: * @version 1.0
38: */
39: public interface BandWidth extends Field {
40:
41: /** "Conference Total" bandwidth modifier, "CT".
42: */
43: public static final String CT = "CT";
44:
45: /** "Application Specific" bandwidth modifier, "AS".
46: */
47: public static final String AS = "AS";
48:
49: /** Returns the bandwidth type.
50: */
51: public String getType() throws SdpParseException;
52:
53: /** Sets the bandwidth type.
54: */
55: public void setType(String type) throws SdpException;
56:
57: /** Returns the bandwidth value measured in kilobits per second.
58: */
59: public int getValue() throws SdpParseException;
60:
61: /** Sets the bandwidth value.
62: */
63: public void setValue(int value) throws SdpException;
64:
65: }
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