In this mode, data and its error-correcting code are sent with the connection request
ASYN at the same time. The ASYN only plays the role of informing the next node that
should be ready for data receiving, inspecting and error-correcting, forwarding, but
need not confirming. After the data is sent, a one-way connection is removed when
time is out, without sending an AFIN signaling.
3.4 Efficient Transmission Mode
Efficient transmission mode establishes a direct link between the source node and
destination node. At the same time, link service is called directly across the underlying
network layer after packets of transport layer are encapsulated by the link-layer packets
to ensure near real-time transport services for small-capacity data.
In order to improve the adaptability of the network, and to provide awareness of
requirements from the application layer, different periods of life are set up, and three
strategies such as “low delay, high reliability, and large throughput” are provided.
(1) Order and text information: because of the small amount, but high-reliability
requirements, adopt “high reliability” strategy, using segment-reliable transmission
mode, where, the path is divided into multiple segments which are relatively stable.
And in each segment, the improved transmission mode is used, to ensure the
reliability of information transmission under the high dynamic environment.
(2) Image and the streaming media information: because of the large amount and strict
time delay requirement, adopt “big throughput” strategy, using half-reliable
transmission mode, to improve the throughput of overall transmission for interflight ad hoc networks, and to guarantee the reliability of the large-capacity
information transmission.
(3) Control information: because the little amount and nearly real-time requirements,
adopt “low latency” strategy, using efficient transmission mode, namely the linklayer header encapsulation is used for transport layer packet directly, and then the
packet is sent through direct link with higher power, to reduce the time costs of
forwarding, ensuring the timeliness of control information transmission.
4 Comparison Analysis
Based on the OPNET 14.5 simulation platform, the M
2 T simulation software for interflight ad hoc networks is developed. Compared with the traditional TCP, the validity of
M
2 T is verified by simulation.
4.1 Validity of M
2 T
The packet loss rate and bandwidth occupancy of M
2 T are tested with different link
quality. Simulation scenario is set as follows: link error rate is in a range from
0.1 to 5.0%; the maximum packet delay allowed is 300 ms (a packet, whose delay is
over 300 ms, is invalid and will be discarded directly); One-way network delay is 50–
75 ms, it means that a packet can be retransmitted once or twice.
A Transmission Method for Intra-flight Ad Hoc Networks …
365
ASYN at the same time. The ASYN only plays the role of informing the next node that
should be ready for data receiving, inspecting and error-correcting, forwarding, but
need not confirming. After the data is sent, a one-way connection is removed when
time is out, without sending an AFIN signaling.
3.4 Efficient Transmission Mode
Efficient transmission mode establishes a direct link between the source node and
destination node. At the same time, link service is called directly across the underlying
network layer after packets of transport layer are encapsulated by the link-layer packets
to ensure near real-time transport services for small-capacity data.
In order to improve the adaptability of the network, and to provide awareness of
requirements from the application layer, different periods of life are set up, and three
strategies such as “low delay, high reliability, and large throughput” are provided.
(1) Order and text information: because of the small amount, but high-reliability
requirements, adopt “high reliability” strategy, using segment-reliable transmission
mode, where, the path is divided into multiple segments which are relatively stable.
And in each segment, the improved transmission mode is used, to ensure the
reliability of information transmission under the high dynamic environment.
(2) Image and the streaming media information: because of the large amount and strict
time delay requirement, adopt “big throughput” strategy, using half-reliable
transmission mode, to improve the throughput of overall transmission for interflight ad hoc networks, and to guarantee the reliability of the large-capacity
information transmission.
(3) Control information: because the little amount and nearly real-time requirements,
adopt “low latency” strategy, using efficient transmission mode, namely the linklayer header encapsulation is used for transport layer packet directly, and then the
packet is sent through direct link with higher power, to reduce the time costs of
forwarding, ensuring the timeliness of control information transmission.
4 Comparison Analysis
Based on the OPNET 14.5 simulation platform, the M
2 T simulation software for interflight ad hoc networks is developed. Compared with the traditional TCP, the validity of
M
2 T is verified by simulation.
4.1 Validity of M
2 T
The packet loss rate and bandwidth occupancy of M
2 T are tested with different link
quality. Simulation scenario is set as follows: link error rate is in a range from
0.1 to 5.0%; the maximum packet delay allowed is 300 ms (a packet, whose delay is
over 300 ms, is invalid and will be discarded directly); One-way network delay is 50–
75 ms, it means that a packet can be retransmitted once or twice.
A Transmission Method for Intra-flight Ad Hoc Networks …
365