struct XUDPHost
{
int fdAudio; /* File descriptor of UNIX Stream */
int fdVideo; /* File descriptor of UNIX Stream */
int fdControl; /* File descriptor of UNIX
Stream */
struct sockaddr_in hostaddr;
struct hostent *pHostent; /* hostent structure for client */
};
XUDPHost structure.
struct XUDPPacket
{
struct XUDPHeader header; /* Header information */
u_short length; /* Length in bytes of
payload + header */
Boolean ack; /* Has packet been ACKed? */
u_char payload[MAXPAYLOAD]; /* Duplicates Header with
Network byte ordering */
struct XUDPPacket *prev;
struct XUDPPacket *next;
};
XUDPPacket structure.
struct XUDPHeader
{
Options options; /* Options field */
u_char cmds; /* Number of commands present at end of */
/* header */
Window window; /* Advertised window size */
Timestamp timestamp; /* Packet timestamp field */
Timestamp tto; /* Time to obsolescence timestamp field */
Sequence sequence; /* Packet in-parcel sequence number */
Sequence parcel; /* Parcel sequence number */
u_short length; /* Length of payload */
};
XUDPHeader structure.
\begin{center}
struct XUDPParcel
{
Sequence parcel; /* Sequence number of parcel */
Options options; /* High-level options field */
Timestamp tto; /* Time to obsolescence timestamp */
/* field */
Timestamp timestamp; /* Parcel creation timestamp */
u_short length; /* Length of data buffer */
char *buffer; /* Pointer to data buffer */
char *pos; /* Current position in buffer */
struct XUDPParcel *prev;
struct XUDPParcel *next;
};
XUDPParcel structure.
struct XUDPFragParcel
{
Sequence parcel; /* Sequence number of the parcel */
Options options; /* High-level options field */
Timestamp tto; /* Time to obsolescence timestamp */
/* field */
Timestamp timestamp; /* Parcel creation timestamp */
Sequence end; /* Ending packet number */
Boolean ack; /* Has parcel been ACKed */
struct XUDPPacket *headPacket; /* Beginning of packet list */
struct XUDPFragParcel *prev;
struct XUDPFragParcel *next;
};
XUDPFragParcel structure.
struct XUDPCmd
{
u_char cmd; /* Command ID */
char length; /* Length in bytes of argbuffer */
Timestamp timestamp;
char *argbuffer; /* Command argument data */
struct XUDPCmd *next;
struct XUDPCmd *prev;
};
XUDPCmd structure.
struct XUDPCB
{
int fdCli; /* Socket fd for UDP Client */
struct sockaddr_in hostaddr; /* Address structure for remote */
struct XUDPFragParcel *pAckWaitQueue; /* head of parcels waiting */
/* for ACKS*/
struct XUDPParcel *pOutHead; /* head of outgoing queue */
struct XUDPFragParcel *pRecvWaitQueue; /* head of received parcels */
struct XUDPParcel *pInHead; /* head of assembled parcels */
struct XUDPPacket *pXmitQueue; /* Outgoing packets */
struct XUDPPacket *pRecvQueue; /* Incoming packets */
struct XUDPCmd *pCmdQueue; /* head of queued up
commands to be
transmitted over the
network */
struct XUDPCmd *pCmdInQueue; /* head of incoming commands */
struct XUDPHost *localclient; /* Local application */
struct sockaddr_un addrAudio_un; /* Address structures for */
struct sockaddr_un addrVideo_un; /* UNIX streams used */
struct sockaddr_un addrControl_un;
enum XUDPState state; /* State of the XUDP */
/* connection */
Boolean push; /* XUDP PUSH flag */
u_short mps; /* Current MPS */
Window winAdvertised; /* Local advertised window */
Window winCongestion; /* Local congestion window */
float winFCongestion; /* Floating point version of */
/* congestion window */
Window winRemote; /* Remote advertised window */
Window packetsInPipe; /* Packets in network from us */
Window packetsInPipeRmt; /* Packets in network from */
/* them, we perceive */
Timestamp rtt; /* Current Round Trip Time */
float rttavg; /* Average RTT */
float rttvar; /* Current RTT Variance */
float rttmax; /* Decaying Max RTT */
float rttmin; /* Decaying Min RTT */
Timestamp rto; /* Current Retransmission */
/* Time Out Timer */
unsigned long int bytesSent; /* Bytes sent during this */
/* session */
unsigned long int bytesACKed; /* Bytes ACKed during this */
/* session */
Timestamp timeElapsed; /* Elapsed time for this */
/* session */
unsigned int bandwidth; /* Calculated average bandwidth */
/* usage */
float windowdelta; /* Indicates the rate of */
/* change of the congestion */
/* window */
Boolean usedparcels[MAXPARCEL]; /* Keeps track of used */
/* parcel numbers */
Timestamp closing; /* Gets set upon invocation */
/* of XUDP_CLOSE_WAIT state */
};
XUDPCB ``control block'' structure.
struct XUDPSCB
{
struct sockaddr_in addrServ_in; /* Local UDP Server */
int fdServ; /* Socket fd for UDP Server */
int fdServAudio; /* Socket fd for UNIX Audio */
/* Stream */
int fdServVideo; /* UNIX Video stream */
int fdServControl; /* UNIX Control data stream */
struct sockaddr_un addrServAudio_un; /* UNIX Address structure for the
audio stream server */
struct sockaddr_un addrServVideo_un; /* Video stream server */
struct sockaddr_un addrServControl_un; /* Control stream server */
};
XUDPSCB ``server control block'' structure.