在NS2中添加路由协议（整理版）1

TOMATOFAN

最近正在研究怎样把自己新写的协议添加到NS2中去，正好借鉴了一些朋友的文章，现在整理下来，以便以后参考，也希望能给广大博友一些方便。
step 1：比如我们新建的协议名字就叫做protoname，以ns2.27平台为例，我们在ns2.27目录下建立一个protoname目录。此目录包含protoname.h，protoname.cc，protoname_pkt.h，protoname_rtable.h，protoname_rtable.cc五个文件。
其中五个文件的具体功能和作用如下：
（1）protoname.h 定义必要的计时器和路由代理
（2）protoname.cc 执行计时器、路由代理和Tcl文件
（3）protoname_pkt.h 声明protoname路由协议需要在无线自组网节点交换的数据包
（4）protoname_rtable.h 声明我们自己的路由选择表
（5）protoname_rtable.cc 执行路由选择表
step 2：相应文件的代码
（1）protoname.h

1. #ifndef __protoname_h__
2. #define __protoname_h__
3. // 下面包含一些需要的头文件
4. #include "protoname_pkt.h" //数据包报头
5. #include "protoname_rtable.h"
6. #include <agent.h> //代理基本类
7. #include <packet.h> //数据包类
8. #include <trace.h> //跟踪类，用于在跟踪文件里记录输出的仿真结果
9. #include <timer-handler.h> //计时器基本类，创建我们自定义的计时器
10. #include <random.h> //随机类，用于产生伪随机数
11. #include <classifier-port.h> //端口分类器类，用于淘汰向上层传输的数据包
12. #include <mobilenode.h>
13. #include "arp.h"
14. #include "ll.h"
15. #include "mac.h"
16. #include "ip.h"
17. #include "delay.h"
18. #define CURRENT_TIME Scheduler::instance().clock() //定义了一个用于得到当前仿真时间的宏
19. //通过一个调度类的实例完成
20. #define JITTER (Random::uniform()*0.5) //在0-0.5之间去随机数作为发送数据的延迟时间
21. class Protoname; // forward declaration
22. /* Timers */ //自定义计时器发送定时的控制包
23. class Protoname_PktTimer : public TimerHandler {
24. public:
25. Protoname_PktTimer(Protoname* agent) : TimerHandler() {
26. agent_ = agent;
27. }
28. protected:
29. Protoname* agent_;
30. virtual void expire(Event* e);
31. };
32. /* Agent */ //定义Protoname 类
33. class Protoname : public Agent {
34. /* Friends */
35. friend class Protoname_PktTimer;
36. /* Private members */ //封装了自身的地址、内状态、路由表、可变的Tcl
37. //以及一个负责指定输出数量的计数器
38. nsaddr_t ra_addr_;
39. //protoname_state state_;
40. protoname_rtable rtable_;
41. int accesible_var_; //用来读取Tcl代码或脚本语言
42. u_int8_t seq_num_;
43. protected:
44. MobileNode* node_;
45. PortClassifier* dmux_; // For passing packets up to agents.端口分类器
46. Trace* logtarget_; // For logging.跟踪器
47. Protoname_PktTimer pkt_timer_; // Timer for sending packets.自定义计时器
48. //内部属性
49. inline nsaddr_t& ra_addr() { return ra_addr_; }
50. //inline protoname_state& state() { return state_; }
51. inline int& accessible_var() { return accesible_var_; }
52. void forward_data(Packet*); //数据包被正确传输的目的地
53. void recv_protoname_pkt(Packet*);
54. void send_protoname_pkt();
55. void reset_protoname_pkt_timer();
56. public:
57. Protoname(nsaddr_t);
58. int command(int, const char*const*);
59. void recv(Packet*, Handler*);
60. //void mac_failed(Packet*);
61. };
62. #endif

（2）protoname.cc

1. #include "protoname.h"
2. #include "protoname_pkt.h"
3. #include <random.h>
4. #include <cmu-trace.h>
5. #include <iostream>
6. int hdr_protoname_pkt::offset_;
7. static class ProtonameHeaderClass : public PacketHeaderClass {
8. public:
9. ProtonameHeaderClass() : PacketHeaderClass("PacketHeader/Protoname", sizeof(hdr_protoname_pkt)) {
10. bind_offset(&hdr_protoname_pkt::offset_);
11. }
12. } class_rtProtoProtoname_hdr;
13. static class ProtonameClass : public TclClass {
14. public:
15. ProtonameClass() : TclClass("Agent/Protoname") {}
16. TclObject* create(int argc, const char*const* argv) {
17. assert(argc == 5);
18. return (new Protoname((nsaddr_t) Address::instance().str2addr(argv[4])));
19. }
20. } class_rtProtoProtoname;
21. void
22. Protoname_PktTimer::expire(Event* e) {
23. agent_->send_protoname_pkt();
24. agent_->reset_protoname_pkt_timer();
25. }
26. Protoname::Protoname(nsaddr_t id) : Agent(PT_PROTONAME), pkt_timer_(this) {
27. bind_bool("accesible_var_", &accesible_var_);
28. ra_addr_ = id;
29. node_ = (MobileNode*)Node::get_node_by_address(id);
30. }
31. int
32. Protoname::command(int argc, const char*const* argv) {
33. if (argc == 2) {
34. if (strcasecmp(argv[1], "start") == 0) {
35. pkt_timer_.resched(0.0);
36. return TCL_OK;
37. }
38. else if (strcasecmp(argv[1], "print_rtable") == 0) {
39. if (logtarget_ != 0) {
40. sprintf(logtarget_->pt_->buffer(), "P %f _%d_ Routing Table", CURRENT_TIME, ra_addr());
41. logtarget_->pt_->dump();
42. rtable_.print(logtarget_);
43. }
44. else {
45. fprintf(stdout, "%f _%d_ If you want to print this routing table "
46. "you must create a trace file in your tcl script", CURRENT_TIME, ra_addr());
47. }
48. return TCL_OK;
49. }
50. }
51. else if (argc == 3) {
52. // Obtains corresponding dmux to carry packets to upper layers
53. if (strcmp(argv[1], "port-dmux") == 0) {
54. dmux_ = (PortClassifier*)TclObject::lookup(argv[2]);
55. if (dmux_ == 0) {
56. fprintf(stderr, "%s: %s lookup of %s failed\n", __FILE__, argv[1], argv[2]);
57. return TCL_ERROR;
58. }
59. return TCL_OK;
60. }
61. // Obtains corresponding tracer
62. else if (strcmp(argv[1], "log-target") == 0 || strcmp(argv[1], "tracetarget") == 0) {
63. logtarget_ = (Trace*)TclObject::lookup(argv[2]);
64. if (logtarget_ == 0)
65. return TCL_ERROR;
66. return TCL_OK;
67. }
68. }
69. // Pass the command to the base class
70. return Agent::command(argc, argv);
71. }
72. void
73. Protoname::recv(Packet* p, Handler* h) {
74. struct hdr_cmn* ch = HDR_CMN(p);
75. struct hdr_ip* ih = HDR_IP(p);
76. if (ih->saddr() == ra_addr()) {
77. // If there exists a loop, must drop the packet
78. if (ch->num_forwards() > 0) {
79. drop(p, DROP_RTR_ROUTE_LOOP);
80. return;
81. }
82. // else if this is a packet I am originating, must add IP header
83. else if (ch->num_forwards() == 0)
84. ch->size() += IP_HDR_LEN;
85. }
86. // If it is a protoname packet, must process it
87. if (ch->ptype() == PT_PROTONAME)
88. recv_protoname_pkt(p);
89. // Otherwise, must forward the packet (unless TTL has reached zero)
90. else {
91. ih->ttl_--;
92. if (ih->ttl_ == 0) {
93. drop(p, DROP_RTR_TTL);
94. return;
95. }
96. forward_data(p);
97. }
98. }
99. void
100. Protoname::recv_protoname_pkt(Packet* p) {
101. struct hdr_ip* ih = HDR_IP(p);
102. struct hdr_protoname_pkt* ph = HDR_PROTONAME_PKT(p);
103. // All routing messages are sent from and to port RT_PORT,
104. // so we check it.
105. assert(ih->sport() == RT_PORT);
106. assert(ih->dport() == RT_PORT);
107. /* ... processing of protoname packet ... */
108. // Release resources
109. Packet::free(p);
110. }
111. void
112. Protoname::send_protoname_pkt() {
113. Packet* p = allocpkt();
114. struct hdr_cmn* ch = HDR_CMN(p);
115. struct hdr_ip* ih = HDR_IP(p);
116. struct hdr_protoname_pkt* ph = HDR_PROTONAME_PKT(p);
117. ph->pkt_src() = ra_addr();
118. ph->pkt_len() = 7;
119. ph->pkt_seq_num() = seq_num_++;
120. ch->ptype() = PT_PROTONAME;
121. ch->direction() = hdr_cmn::DOWN;
122. ch->size() = IP_HDR_LEN + ph->pkt_len();
123. ch->error() = 0;
124. ch->next_hop() = IP_BROADCAST;
125. ch->addr_type() = NS_AF_INET;
126. ih->saddr() = ra_addr();
127. ih->daddr() = IP_BROADCAST;
128. ih->sport() = RT_PORT;
129. ih->dport() = RT_PORT;
130. ih->ttl() = IP_DEF_TTL;
131. Scheduler::instance().schedule(target_, p, JITTER);
132. }
133. void
134. Protoname::reset_protoname_pkt_timer() {
135. pkt_timer_.resched((double)5.0);
136. }
137. void
138. Protoname::forward_data(Packet* p) {
139. struct hdr_cmn* ch = HDR_CMN(p);
140. struct hdr_ip* ih = HDR_IP(p);
141. if (ch->direction() == hdr_cmn::UP &&
142. ((u_int32_t)ih->daddr() == IP_BROADCAST || ih->daddr() == ra_addr())) {
143. dmux_->recv(p, 0);
144. return;
145. }
146. else {
147. ch->direction() = hdr_cmn::DOWN;
148. ch->addr_type() = NS_AF_INET;
149. if ((u_int32_t)ih->daddr() == IP_BROADCAST)
150. ch->next_hop() = IP_BROADCAST;
151. else {
152. nsaddr_t next_hop = rtable_.lookup(ih->daddr());
153. if (next_hop == IP_BROADCAST) {
154. debug("%f: Agent %d can not forward a packet destined to %d\n",
155. CURRENT_TIME,
156. ra_addr(),
157. ih->daddr());
158. drop(p, DROP_RTR_NO_ROUTE);
159. return;
160. }
161. else
162. ch->next_hop() = next_hop;
163. }
164. Scheduler::instance().schedule(target_, p, 0.0);
165. }
166. }
167. （3）protoname_pkt.h
168. #ifndef __protoname_pkt_h__
169. #define __protoname_pkt_h__
170. #include <packet.h>
171. #define HDR_PROTONAME_PKT(p) hdr_protoname_pkt::access(p)
172. struct hdr_protoname_pkt {
173. nsaddr_t pkt_src_; // Node which originated this packet
174. u_int16_t pkt_len_; // Packet length (in bytes)
175. u_int8_t pkt_seq_num_; // Packet sequence number
176. inline nsaddr_t& pkt_src() { return pkt_src_; }
177. inline u_int16_t& pkt_len() { return pkt_len_; }
178. inline u_int8_t& pkt_seq_num() { return pkt_seq_num_; }
179. static int offset_;
180. inline static int& offset() { return offset_; }
181. inline static hdr_protoname_pkt* access(const Packet* p) {
182. return (hdr_protoname_pkt*)p->access(offset_);
183. }
184. };
185. #endif
186. （4）protoname_rtable.h
187. #ifndef __protoname_rtable_h__
188. #define __protoname_rtable_h__
189. #include <trace.h>
190. #include <map>
191. typedef std::map<nsaddr_t, nsaddr_t> rtable_t;
192. class protoname_rtable {
193. rtable_t rt_;
194. public:
195. protoname_rtable();
196. void print(Trace*);
197. void clear();
198. void rm_entry(nsaddr_t);
199. void add_entry(nsaddr_t, nsaddr_t);
200. nsaddr_t lookup(nsaddr_t);
201. u_int32_t size();
202. };
203. #endif
204. （5）protoname_rtable.cc
205. #include "protoname_rtable.h"
206. #include "ip.h"
207. protoname_rtable::protoname_rtable() { }
208. void
209. protoname_rtable::print(Trace* out) {
210. sprintf(out->pt_->buffer(), "P\tdest\tnext");
211. out->pt_->dump();
212. for (rtable_t::iterator it = rt_.begin(); it != rt_.end(); it++) {
213. sprintf(out->pt_->buffer(), "P\t%d\t%d", (*it).first, (*it).second);
214. out->pt_->dump();
215. }
216. }
217. void
218. protoname_rtable::clear() {
219. rt_.clear();
220. }
221. void
222. protoname_rtable::rm_entry(nsaddr_t dest) {
223. rt_.erase(dest);
224. }
225. void
226. protoname_rtable::add_entry(nsaddr_t dest, nsaddr_t next) {
227. rt_[dest] = next;
228. }
229. nsaddr_t
230. protoname_rtable::lookup(nsaddr_t dest) {
231. rtable_t::iterator it = rt_.find(dest);
232. if (it == rt_.end())
233. return IP_BROADCAST;
234. else
235. return (*it).second;
236. }
237. u_int32_t
238. protoname_rtable::size() {
239. return rt_.size();
240. }

step 3：我们需要对ns2中的一些文件进行修改，来使这个协议在tcl中被调用，

需要修改的文件有以下几个,你可以在ns目录下找到它们：

Common/packet.h

Trace/cmu-trace.h

Trace/cmu-trace.cc

Tcl/lib/ns-packet.tcl

Tcl/lib/ns-default.tcl

Tcl/lib/ns-lib.tcl

Queue/priqueue.cc

Makefile

step4：需要修改的具体内容（在需要修改的地方添加红色的字）

1.Common/packet.h （两个需要修改的地方）

1: enum packet_t {

2: PT_TCP,

3: PT_UDP,

4: PT_CBR,

5: /* ... much more packet types ... */

6: PT_PROTONAME,

7: PT_NTYPE // This MUST be the LAST one

8: };

=======================================

1: p_info() {

2: name_[PT_TCP]= "tcp";

3: name_[PT_UDP]= "udp";

4: name_[PT_CBR]= "cbr";

5: /* ... much more names ... */

6: name_[PT_PROTONAME]= "protoname";

7: }

2.Trace/cmu-trace.h （一个）

1: class CMUTrace : public Trace {

2: /* ... definitions ... */

3: private:

4: /* ... */

5: void format_aodv(Packet *p, int offset);

6: void format_protoname(Packet *p, int offset);

7: };

3.Trace/cmu-trace.cc （三个，先在最上面加头文件，在找一个合适的地方加函数）

1: #include <protoname/protoname_pkt.h>

2:

3: /* ... */

4:

5: void

6: CMUTrace::format_protoname(Packet *p, int offset)

7: {

8: struct hdr_protoname_pkt* ph = HDR_PROTONAME_PKT(p);

9:

10: if (pt_->tagged()) {

11: sprintf(pt_->buffer() + offset,

12: "-protoname:o %d -protoname:s %d -protoname:l %d ",

13: ph->pkt_src(),

14: ph->pkt_seq_num(),

15: ph->pkt_len());

16: }

17: else if (newtrace_) {

18: sprintf(pt_->buffer() + offset,

19: "-P protoname -Po %d -Ps %d -Pl %d ",

20: ph->pkt_src(),

21: ph->pkt_seq_num(),

22: ph->pkt_len());

23: }

24: else {

25: sprintf(pt_->buffer() + offset,

26: "[protoname %d %d %d] ",

27: ph->pkt_src(),

28: ph->pkt_seq_num(),

29: ph->pkt_len());

30: }

31: }

=========================================

1: void

2: CMUTrace::format(Packet* p, const char *why)

3: {

4: /* ... */

5: case PT_PING:

6: break;

7:

8: case PT_PROTONAME:

9: format_protoname(p, offset);

10: break;

11:

12: default:

13: /* ... */

14: }

4.Tcl/lib/ns-packet.tcl（一个）

1: foreach prot {

2: Protoname

3: AODV

4: ARP

5: # ...

6: NV

7: } {

8: add-packet-header $prot

9: }

 

5.Tcl/lib/ns-default.tcl（一个）

1: # ...

2: # Defaults defined for Protoname

3: Agent/Protoname set accessible_var_ true

6.Tcl/lib/ns-lib.tcl（两个）

1: Simulator instproc create-wireless-node args {

2: # ...

3: switch -exact $routingAgent_ {

4: Protoname {

5: set ragent [$self create-protoname-agent $node]

6: }

7: # ...

8: }

9: # ...

10: }

=======================================

1: Simulator instproc create-protoname-agent { node } {

2: # Create Protoname routing agent

3: set ragent [new Agent/Protoname [$node node-addr]]

4: $self at 0.0 "$ragent start"

5: $node set ragent_ $ragent

6: return $ragent

7: }

7.Queue/priqueue.cc（一个）

1: void

2: PriQueue::recv(Packet *p, Handler *h)

3: {

4: struct hdr_cmn *ch = HDR_CMN(p);

5:

6: if (Prefer_Routing_Protocols) {

7:

8: switch(ch->ptype()) {

9: case PT_DSR:

10: case PT_MESSAGE:

11: case PT_TORA:

12: case PT_AODV:

13: case PT_PROTONAME:

14: recvHighPriority(p, h);

15: break;

16:

17: default:

18: Queue::recv(p, h);

19: }

20: }

21: else {

22: Queue::recv(p, h);

23: }

24: }

8.Makefile（一个）

1: OBJ_CC = \

2: tools/random.o tools/rng.o tools/ranvar.o common/misc.o common/timer-handler.o \

3: # ...

4: protoname/protoname.o protoname/protoname_rtable.o \

5: # ...

6: $(OBJ_STL)

step 5：编译

在ns目录下输入下名命令进行编译：

$ make clean

$ touch common/packet.cc

$ make

到这里，我们添加新协议的过程就结束了。

step 6：测试

协议写完了，要用一个tcl对它进行测试，下面这是个很简单的而且可用的例子

set ns [new Simulator]

$ns node-config -Routing protoname  

set nf [open out.nam w]    

$ns namtrace-all $nf      

set nd [open out.tr w]      

$ns trace-all $nd            

  proc finish {} {

          global ns nf  nd

          $ns flush-trace

          close $nf      

          close $nd      

          exec nam out.nam &

          exit 0

   }

 

for {set i 0} {$i < 7} {incr i} {set n($i) [$ns node] }

for {set i 0} {$i < 7} {incr i} {

$ns duplex-link $n($i) $n([expr ($i+1)%7]) 1Mb 10ms DropTail

}

set udp0 [new Agent/UDP]  

$ns attach-agent $n(0) $udp0

set cbr0 [new Application/Traffic/CBR]

$cbr0 set packetSize_ 500    

$cbr0 set interval_ 0.005     

$cbr0 attach-agent $udp0

set null0 [new Agent/Null]

$ns attach-agent $n(3) $null0

$ns connect $udp0 $null0

$ns at 0.5 "$cbr0 start"

$ns rtmodel-at 1.0 down $n(1) $n(2)

$ns rtmodel-at 2.0 up $n(1) $n(2)  

$ns at 4.5 "$cbr0 stop"

$ns at 5.0 "finish"

$ns run

参考文献：

[1]Implementing a New Manet Unicast Routing Protocol in NS2，Francisco J. Ros  Pedro M. Ruiz

[2]http://ourlab.blog.sohu.com/64266258.html