diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..de476b2
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,11 @@
+# NOTE: Feel free to change the makefile to suit your own need.
+
+# compile and link flags
+CC=g++
+
+all: 
+	g++ -std=c++0x -pthread dsdv.cpp rip.cpp socket.cpp -o dsdv
+
+
+clean:
+	rm -f *~ *.o dsdv
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..aadb2ff
--- /dev/null
+++ b/README.md
@@ -0,0 +1,44 @@
+
+
+文件构成：
+	本次lab主要由5个文件构成
+	socket.h & socket.cpp用来提供udp socket方面的接口和实现，具体内容可以参考socket.h
+	
+	rip.h & rip.cpp用来提供路由算法的接口和实现，主要包含两个struct和6个函数接口
+	
+		struct RouterTab:用来保存路由表中每一行的数据，其中seqNum表示重点的seqNum
+		struct Host:用来表示主机，包括主机的名称，seqNum和路由表的行数
+		
+		void ripInit(string filename, map<string, struct RouterTab> &table, map<int, string> &adjTab, struct Host &host)
+			用来初始化路由器，从filename中读入表项并将其保存到table中，将端口号和名称的映射保存在adjTab中，将host信息保存到host中
+		void ripSend(string &content, map<string, struct RouterTab> &table, struct Host &host)
+			用来住准备发送内容，将主机信息和路由表转换成string保存到content中
+		void ripUpdate(struct Host from, map<string, struct RouterTab> &srcTab, map<string, struct RouterTab> &adjTable, map<string, struct RouterTab> &routeTable, struct Host &host)
+			当收到邻节点from的路由表srcTab是，根据主机保存的信息更新
+		void ripRefresh(map<string, struct RouterTab> &bufferdAdj, map<string, struct RouterTab> &newAdj, map<string, struct RouterTab> &table, struct Host &host)
+			根据重新从磁盘读入的newAdj和之前保存的bufferAdj来更新host的信息
+		void ripReceive(string content, map<string, struct RouterTab> &srcTab, struct Host &from);
+			将收到邻节点的content信息转换成srcTab的路由表和from的路由器信息
+		void ripPrintTable(map<string, struct RouterTab> &table, int &printNum, struct Host &host)
+			打印主机信息
+			
+	
+	dsdv.cpp
+		模拟路由器本身，采用双线程的方式，一个线程用来监听udp端口，接受并且更新路由表。另一个线程用来定时刷新路由表并且发送。详细参见dsdv.cpp
+			
+路由表查找及更新的算法
+	采用了dsdv的基本思路，通过seqNum来表示路由的最新状态。路径中的seqNum代表末节点的seqNum，其中如果seqNum是奇数，表示路由器正处在中间状态，他不能被更新，也不能更新其他路由器
+	1.从硬盘刷新路由表：从硬盘读取新数据，比对路由器缓存的旧表（adjBuf），如果有变动，将自己的seqNum ++，同时将所有的到邻节点的路全部强制刷新成直接链接。并且更新路由表中所有通过邻节点的路径的cost。
+	2.从邻节点更新路由表：首先存在4中情况：1.from seqNum 为偶数，host 为偶数；2.from 偶数，host奇数；3.from 奇数，host 奇数；4.from 奇数， host 偶数；
+		对于1.from为中间状态，忽略
+		2.host处于中间状态，忽略
+		3.表示from和host正好是更新的边的两端点，更新到对应路径的seqNum，并且自身的seqNum ++
+		4.又可以分为两种子情况，如果from的路由表中到自己的路线的seqNum为奇数，更行他的seqNum，此时中间状态完全结束，否则进行正常更新步骤
+		由于硬盘刷新策略的设计是全部换成直连，所以当host路由表中发现from的seqNum大于路由表中保存的信息时，从buffer的邻节点表中更新所有到邻节点的路径。并且对路由表的路径也进行重新计算
+		如果发现相等，对于所有路径进行更新：如果from中终点的seqNum较大，强制更新。否则重新计算路径的cost，以及判断是否改变路由路线从而获取最优值
+		
+	对于这个算法，只要有路线变化，他们的影响就会从变化的两个端点扩散出去，最差的情况可能就是整张路由表全部直间连接（相当与重建），然后逐步优化到最优，虽然效率一般，但是实现比较方便。
+	
+			
+	
+
diff --git a/README~ b/README~
new file mode 100644
index 0000000..200df01
--- /dev/null
+++ b/README~
@@ -0,0 +1,46 @@
+ID:	5110379042
+Name:	付周望
+E-mail:	frankfzw@sjtu.edu.cn
+
+文件构成：
+	本次lab主要由5个文件构成
+	socket.h & socket.cpp用来提供udp socket方面的接口和实现，具体内容可以参考socket.h
+	
+	rip.h & rip.cpp用来提供路由算法的接口和实现，主要包含两个struct和6个函数接口
+	
+		struct RouterTab:用来保存路由表中每一行的数据，其中seqNum表示重点的seqNum
+		struct Host:用来表示主机，包括主机的名称，seqNum和路由表的行数
+		
+		void ripInit(string filename, map<string, struct RouterTab> &table, map<int, string> &adjTab, struct Host &host)
+			用来初始化路由器，从filename中读入表项并将其保存到table中，将端口号和名称的映射保存在adjTab中，将host信息保存到host中
+		void ripSend(string &content, map<string, struct RouterTab> &table, struct Host &host)
+			用来住准备发送内容，将主机信息和路由表转换成string保存到content中
+		void ripUpdate(struct Host from, map<string, struct RouterTab> &srcTab, map<string, struct RouterTab> &adjTable, map<string, struct RouterTab> &routeTable, struct Host &host)
+			当收到邻节点from的路由表srcTab是，根据主机保存的信息更新
+		void ripRefresh(map<string, struct RouterTab> &bufferdAdj, map<string, struct RouterTab> &newAdj, map<string, struct RouterTab> &table, struct Host &host)
+			根据重新从磁盘读入的newAdj和之前保存的bufferAdj来更新host的信息
+		void ripReceive(string content, map<string, struct RouterTab> &srcTab, struct Host &from);
+			将收到邻节点的content信息转换成srcTab的路由表和from的路由器信息
+		void ripPrintTable(map<string, struct RouterTab> &table, int &printNum, struct Host &host)
+			打印主机信息
+			
+	
+	dsdv.cpp
+		模拟路由器本身，采用双线程的方式，一个线程用来监听udp端口，接受并且更新路由表。另一个线程用来定时刷新路由表并且发送。详细参见dsdv.cpp
+			
+路由表查找及更新的算法
+	采用了dsdv的基本思路，通过seqNum来表示路由的最新状态。路径中的seqNum代表末节点的seqNum，其中如果seqNum是奇数，表示路由器正处在中间状态，他不能被更新，也不能更新其他路由器
+	1.从硬盘刷新路由表：从硬盘读取新数据，比对路由器缓存的旧表（adjBuf），如果有变动，将自己的seqNum ++，同时将所有的到邻节点的路全部强制刷新成直接链接。并且更新路由表中所有通过邻节点的路径的cost。
+	2.从邻节点更新路由表：首先存在4中情况：1.from seqNum 为偶数，host 为偶数；2.from 偶数，host奇数；3.from 奇数，host 奇数；4.from 奇数， host 偶数；
+		对于1.from为中间状态，忽略
+		2.host处于中间状态，忽略
+		3.表示from和host正好是更新的边的两端点，更新到对应路径的seqNum，并且自身的seqNum ++
+		4.又可以分为两种子情况，如果from的路由表中到自己的路线的seqNum为奇数，更行他的seqNum，此时中间状态完全结束，否则进行正常更新步骤
+		由于硬盘刷新策略的设计是全部换成直连，所以当host路由表中发现from的seqNum大于路由表中保存的信息时，从buffer的邻节点表中更新所有到邻节点的路径。并且对路由表的路径也进行重新计算
+		如果发现相等，对于所有路径进行更新：如果from中终点的seqNum较大，强制更新。否则重新计算路径的cost，以及判断是否改变路由路线从而获取最优值
+		
+	对于这个算法，只要有路线变化，他们的影响就会从变化的两个端点扩散出去，最差的情况可能就是整张路由表全部直间连接（相当与重建），然后逐步优化到最优，虽然效率一般，但是实现比较方便。
+	
+			
+	
+
diff --git a/a.dat b/a.dat
new file mode 100644
index 0000000..481d51a
--- /dev/null
+++ b/a.dat
@@ -0,0 +1,4 @@
+3 a
+b -2.0 3032
+c 5.0 3033
+d 1.0 3034
diff --git a/a.dat~ b/a.dat~
new file mode 100644
index 0000000..82c56de
--- /dev/null
+++ b/a.dat~
@@ -0,0 +1,4 @@
+3 a
+b 2.0 3032
+c 5.0 3033
+d 1.0 3034
diff --git a/b.dat b/b.dat
new file mode 100644
index 0000000..f807cfb
--- /dev/null
+++ b/b.dat
@@ -0,0 +1,4 @@
+3 b
+a -2.0 3031
+c 3.0 3033
+d 2.0 3034
diff --git a/b.dat~ b/b.dat~
new file mode 100644
index 0000000..4231b2d
--- /dev/null
+++ b/b.dat~
@@ -0,0 +1,4 @@
+3 b
+a 2.0 3031
+c 3.0 3033
+d 2.0 3034
diff --git a/c.dat b/c.dat
new file mode 100644
index 0000000..a5125f1
--- /dev/null
+++ b/c.dat
@@ -0,0 +1,6 @@
+5 c
+b 3.0 3032
+d 3.0 3034
+a 5.0 3031
+e 1.0 3035
+f 5.0 3036
diff --git a/d.dat b/d.dat
new file mode 100644
index 0000000..044e5ec
--- /dev/null
+++ b/d.dat
@@ -0,0 +1,5 @@
+4 d
+c 3.0 3033
+e 1.0 3035
+a 1.0 3031
+b 2.0 3032
diff --git a/dsdv b/dsdv
new file mode 100755
index 0000000..c0186c9
Binary files /dev/null and b/dsdv differ
diff --git a/dsdv.cpp b/dsdv.cpp
new file mode 100644
index 0000000..8c759c5
--- /dev/null
+++ b/dsdv.cpp
@@ -0,0 +1,144 @@
+#include "rip.h"
+#include "socket.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <thread>
+#include <mutex>
+#include <pthread.h>
+#include <unistd.h>
+#include <iostream>
+#include <arpa/inet.h>
+#include <sys/socket.h>
+
+using namespace std;
+
+mutex mtx;
+
+//global variable
+
+//store the table from disk temporarily
+map<string, struct RouterTab> myTable;
+
+//store adjacent nods map
+map<string, struct RouterTab> adjBuf;
+
+//store the route table
+map<string, struct RouterTab> routerTable;
+
+//store the map from port number to the name of router
+map<int, string> portToName;
+
+//store the host message
+struct Host host;
+
+//store the socket fd
+int fd;
+
+//store the print time
+int printNum;
+
+
+void* receive(void* ptr)
+{
+	//cout<<"thread 1\n";
+	
+	while(1)
+	{
+		string content;
+		int fromPort = socketReceive(fd, content);
+		//cout<<"receive from: "<<fromPort<<endl;
+		//cout<<"receive content: "<<content<<endl;
+		//cout<<"========================\n";
+		
+		//update route table
+		string src = portToName.find(fromPort)->second;
+		Host srcRouter;
+		srcRouter.name = src;
+		map<string, struct RouterTab> srcTab;
+		
+		//cout<<"========================\n";
+		//cout<<"receive from: "<<src<<endl;
+		//cout<<"receive content: "<<content<<endl;
+		//cout<<"========================\n";
+		
+		ripReceive(content, srcTab, srcRouter);
+		mtx.lock();
+		ripUpdate(srcRouter, srcTab, adjBuf, routerTable, host);
+		mtx.unlock();
+		
+		/*
+		string sentContent;
+		ripSend(sentContent, routerTable);
+		//cout<<sentContent;
+		if(fromPort != -1)
+			socketSend(fd, fromPort, sentContent);
+		*/
+	}
+	
+}
+
+int main(int argc, char *argv[])
+{
+	if(argc != 3)
+	{
+		printf("usage: %s <prot_number> <file_name>\n", argv[0]);
+		exit(-1);
+	}
+	
+	int port = atoi(argv[1]);
+	if(port <= 0)
+	{
+		printf("error: invalid <port_number>\n");
+		exit(-1);
+	}
+	
+	string filename = string(argv[2]);
+	
+	try
+	{
+		//init
+		
+		ripInit(filename, routerTable, portToName, host);
+		ripInit(filename, adjBuf, portToName, host);
+		cout<<"This is router "<<host.name<<" listening port "<<port<<endl;
+	
+		fd = socketBind(port);
+		int fromPort = -1;
+		
+		pthread_t child;
+		pthread_create(&child, NULL, receive, NULL);
+		
+		while(1)
+		{
+			//refresh the table from data
+			Host temp;
+			myTable.clear();
+			mtx.lock();
+			ripInit(filename, myTable, portToName, temp);
+			ripRefresh(adjBuf, myTable, routerTable, host);
+			mtx.unlock();
+			
+			//print table
+			ripPrintTable(routerTable, printNum, host);
+			
+			//prepare to send
+			string sendContent;
+			ripSend(sendContent, routerTable, host);
+			
+			//send router table to adjacent nodes
+			map<int, string>::iterator it = portToName.begin();
+			for(; it != portToName.end(); it ++)
+			{
+				socketSend(fd, it->first, sendContent);
+			}
+			
+			sleep(1);
+		}
+		close(fd);
+	}
+	catch(int e)
+	{
+		cout<<"Oops! error code: "<<e<<endl;
+	}
+    return 0;    
+}
diff --git a/e.dat b/e.dat
new file mode 100644
index 0000000..416e9d4
--- /dev/null
+++ b/e.dat
@@ -0,0 +1,4 @@
+3 e
+d 1.0 3034
+f 2.0 3036
+c 1.0 3033
diff --git a/f.dat b/f.dat
new file mode 100644
index 0000000..ef8ed71
--- /dev/null
+++ b/f.dat
@@ -0,0 +1,3 @@
+2 f
+e 2.0 3035
+c 1.0 3033
diff --git a/make b/make
new file mode 100644
index 0000000..380918a
--- /dev/null
+++ b/make
@@ -0,0 +1 @@
+g++ -std=c++0x -pthread dsdv.cpp rip.cpp socket.cpp -o dsdv
diff --git a/rip.cpp b/rip.cpp
new file mode 100644
index 0000000..8563bf3
--- /dev/null
+++ b/rip.cpp
@@ -0,0 +1,351 @@
+#include <fstream>
+#include <sstream>
+#include "rip.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <cmath>
+#include <iostream>
+
+
+using namespace std;
+
+void ripInit(string filename, map<string, struct RouterTab> &table, map<int, string> &adjTab, struct Host &host)
+{
+	//clear data
+	//table.clear();
+	host.seqNum = 0;
+	host.vectorNum = 0;
+	ifstream ifs;
+	ifs.open(filename.c_str(), ifstream::in);
+
+	if(!ifs.good())
+	{
+		ifs.close();
+		throw NOT_FOUND;
+	}
+
+	int lineNum = 0;
+	string name;
+	ifs>>lineNum>>name;
+	host.name = name;
+	/*RouterTab self;
+	self.dst = name;
+	self.cost = 0;
+	self.hop = name;
+	self.seqNum = 0;
+	table[name] = self;*/
+
+	while(lineNum--)
+	{
+		if(ifs.eof())
+		{
+			ifs.close();
+			throw FILE_ERR;
+		}
+
+		string dst = "";
+		double cost = 0;
+		int portNum = 0;
+		ifs>>dst>>cost>>portNum;
+
+		RouterTab tab = {};
+		tab.dst = dst;
+		if(cost < 0)
+			cost = MAX;
+		tab.cost = cost;
+		tab.hop = dst;
+		tab.seqNum = 0;
+		table[dst] = tab;
+		host.vectorNum ++;
+
+		map<int, string>::iterator it;
+		//if((it = adjTab.find(portNum)) == adjTab.end())
+		adjTab[portNum] = dst;
+
+	}
+
+	ifs.close();
+}
+
+
+void ripSend(string &dst, map<string, struct RouterTab> &table, struct Host &host)
+{
+	ostringstream oss;
+	oss<<host.vectorNum<<endl<<host.seqNum<<endl;
+	map<string, struct RouterTab>::iterator it = table.begin();
+	//int length = 0;
+	for(;it != table.end(); it ++)
+	{
+		oss<<(it->second).dst<<' '<<(it->second).cost<<' '<<(it->second).hop<<' '<<(it->second).seqNum<<'\n';
+		//length ++;
+	}
+	
+	//the head  of the content is the number of router vectors 
+	//ostringstream temp;
+	//temp<<length<<endl;
+	//dst = temp.str();
+	dst = oss.str();
+}
+
+void ripUpdate(struct Host from, map<string, struct RouterTab> &srcTab, map<string, struct RouterTab> &adjTable, map<string, struct RouterTab> &routeTable, struct Host &host)
+{
+	//host is in the intermidate status
+	if(((from.seqNum % 2) == 0) && ((host.seqNum % 2) == 1))
+	{
+		//routh changing successed
+		
+		if((srcTab.find(host.name)->second).seqNum == host.seqNum)
+		{
+			host.seqNum ++;
+			(routeTable.find(from.name)->second).seqNum = from.seqNum;
+		}
+		
+		return;
+	}
+	
+	//from is in the intermidate status
+	if(((from.seqNum % 2) == 1) && ((host.seqNum % 2) == 0))
+	{
+		return;
+	}
+	
+	//from is the exactly one
+	if(((from.seqNum % 2) == 1) && ((host.seqNum % 2) == 1))
+	{
+		host.seqNum ++;
+		(routeTable.find(from.name))->second.seqNum = from.seqNum;
+		return;
+	}
+	
+	//finish the intermidate status
+	if((routeTable.find(from.name)->second).seqNum % 2)
+	{
+		(routeTable.find(from.name)->second.seqNum) = from.seqNum;
+		return;
+	}
+
+	//1st: if from is a new one, change the route to directly
+	if(from.seqNum > (routeTable.find(from.name)->second).seqNum)
+	{
+		(routeTable.find(from.name)->second).seqNum = from.seqNum;
+		//change all route to adj directly
+		map<string, struct RouterTab>::iterator it = adjTable.begin();
+
+		for(; it != adjTable.end(); it ++)
+		{
+			string name = (it->second).dst;
+			double oldCost = (routeTable.find(name)->second).cost;
+			double newCost = (it->second).cost;
+			(routeTable.find(name)->second).cost = newCost;
+			(routeTable.find(name)->second).hop = name;
+			map<string, struct RouterTab>::iterator itt = routeTable.begin();
+			for(; itt != routeTable.end(); itt ++)
+			{
+				if(name.compare((itt->second).dst) == 0)
+					continue;
+				if(name.compare((itt->second).hop) != 0)
+					continue;
+					
+				//cout<<"eeeeeee\t"<<itt->second.cost<<'\t'<<newCost<<'\t'<<oldCost<<endl;	
+				
+				(itt->second).cost += newCost - oldCost;
+				
+				
+				if((itt->second).cost > MAX)
+					(itt->second).cost = MAX;
+			}
+
+		}
+	}
+	else if(from.seqNum == (routeTable.find(from.name)->second).seqNum)
+	{
+		//adj node didn't finish 1st step
+		if((srcTab.find(host.name)->second).seqNum < host.seqNum)
+			return;
+
+		map<string, struct RouterTab>::iterator it;
+		map<string, struct RouterTab>::iterator it2;
+		double fromCost = (routeTable.find(from.name)->second).cost;
+		for(it2 = srcTab.begin(); it2 != srcTab.end(); it2 ++)
+		{
+			string name = (it2->second).dst;
+			string hop = (it2->second).hop;
+			it = routeTable.find(name);
+			
+		
+			//route back to host
+			if(name.compare(host.name) == 0)
+				continue;
+
+			//it's a new route
+			if(it == routeTable.end())
+			{
+				RouterTab temp;
+				temp.dst = name;
+				temp.hop = from.name;
+				double newCost = fromCost + (it2->second).cost;
+				newCost = (newCost > MAX) ? MAX : newCost;
+				temp.cost = newCost;
+				
+				//cout<<"aaaaaaa\t"<<newCost<<endl;
+				
+				temp.seqNum = (it2->second).seqNum;
+				routeTable[name] = temp;
+				host.vectorNum ++;
+			}
+
+			//the route is existed
+			else
+			{
+				//ignore the route which pass by it self
+				if(hop.compare(host.name) == 0)
+					continue;
+
+				//ignore the old route path
+				if((it2->second).seqNum < (it->second).seqNum)
+					continue;
+				
+				//froce updating
+				else if((it2->second).seqNum > (it->second).seqNum)
+				{
+					double newCost = fromCost + (it2->second).cost;
+					newCost = (newCost > MAX) ? MAX : newCost;
+					(it->second).cost = newCost;
+					
+					//cout<<"bbbbbbb\t"<<newCost<<endl;
+					
+					(it->second).seqNum = (it2->second).seqNum;
+					(it->second).hop = from.name;
+				}
+				else
+				{
+					//update route cost and seqNum
+					double newCost = fromCost + (it2->second).cost;
+					newCost = (newCost > MAX) ? MAX : newCost;
+					
+					//cout<<"ccccccc\t"<<fromCost<<'\t'<<(it2->second).cost<<endl;
+					
+					//route don't change, just update the cost
+					if(((it->second).hop).compare(from.name) == 0)
+					{
+						(it->second).cost = newCost;
+						//return;
+					}
+					
+					//new path is better
+					if(newCost < (it->second).cost)
+					{
+						(it->second).cost = newCost;
+						
+						//check if host to from route directly
+						string hopHtoF = (routeTable.find(from.name)->second).hop;
+						if(hopHtoF.compare(from.name) == 0)
+						{
+							(it->second).hop = from.name;
+						}
+						else
+							(it->second).hop = hopHtoF;
+						//cout<<"here!!!!!!!\nfrom:\t"<<from.name<<endl<<it->second.dst<<'\t'<<it->second.hop<<endl;
+						//(it->second).seqNum = srcTab[i].seqNum;
+					}
+			
+				}
+			}
+		}
+	}
+
+
+}
+
+void ripRefresh(map<string, struct RouterTab> &bufferdAdj, map<string, struct RouterTab> &newAdj, map<string, struct RouterTab> &table, struct Host &host)
+{
+	string name;
+	double newCost;
+	double oldCost;
+
+	map<string, struct RouterTab>::iterator it = bufferdAdj.begin();
+	for(; it != bufferdAdj.end(); it ++)
+	{
+		double cost = (it->second).cost;
+		name = (it->second).dst;
+		newCost = (newAdj.find(name)->second).cost;
+		if(abs(cost - newCost) < 0.000001)
+			continue;
+		else
+		{
+			//table.clear();
+			//table = newAdj;
+			//host.seqNum ++;
+			break;
+		}
+	}
+
+	//table didn't change
+	if(it == bufferdAdj.end())
+		return;
+	
+
+	//change all route to adj directly
+	for(it = newAdj.begin(); it != newAdj.end(); it ++)
+	{
+		name = (it->second).dst;
+		newCost = (it->second).cost;
+		oldCost = (table.find(name)->second).cost;
+		(table.find(name)->second).cost = newCost;
+		(table.find(name)->second).hop = name;
+		map<string, struct RouterTab>::iterator itt = table.begin();
+		for(; itt != table.end(); itt ++)
+		{
+			if(name.compare((itt->second).dst) == 0)
+				continue;
+			if(name.compare((itt->second).hop) != 0)
+				continue;
+			(itt->second).cost += newCost - oldCost;
+			
+			//cout<<"ddddddd\t"<<(itt->second).cost<<endl;
+			
+			if((itt->second).cost > MAX)
+				(itt->second).cost = MAX;
+				
+				
+			
+		}
+
+	}
+	bufferdAdj = newAdj;
+	host.seqNum ++;
+}
+
+void ripReceive(string content, map<string, struct RouterTab> &srcTab, struct Host &from)
+{
+	istringstream iss(content);
+
+	iss>>from.vectorNum>>from.seqNum;
+	int length = from.vectorNum;
+
+	while(length --)
+	{
+		RouterTab temp;
+		iss>>temp.dst>>temp.cost>>temp.hop>>temp.seqNum;
+		srcTab[temp.dst] = temp;
+	}
+}
+
+void ripPrintTable(map<string, struct RouterTab> &table, int &printNum, struct Host &host)
+{
+	printNum ++;
+	cout<<"##print-out number\t"<<printNum<<endl;
+	map<string, struct RouterTab>::iterator it = table.begin();
+	for(; it != table.end(); it ++)
+	{
+		string dst = (it->first);
+		string hop = (it->second).hop;
+		int seqNum = (it->second).seqNum;
+		double cost = (it->second).cost;
+		cout<<"shortest path to node "<<dst
+		<<"(seq# "<<seqNum<<"): "
+		<<"the next hop is "<<hop
+		<<" and the cost is "<<cost<<", "
+		<<host.name<<" -> "<<dst<<" : "<<cost<<endl;
+	}
+}
diff --git a/rip.h b/rip.h
new file mode 100644
index 0000000..d8acf93
--- /dev/null
+++ b/rip.h
@@ -0,0 +1,50 @@
+#ifndef _RIP_H_
+#define _RIP_H_
+
+#include <vector>
+#include <string>
+#include <map>
+
+using namespace std;
+
+#define NOT_FOUND 0
+#define FILE_ERR 1
+#define DATA_ERR 2
+#define DATA_UNMATCH 3
+#define MAX 10000
+
+struct RouterTab{
+	string dst;
+	string hop;
+	int seqNum;
+	double cost;
+};
+
+struct Host{
+	string name;
+	int seqNum;
+	int vectorNum;
+};
+
+
+
+/*read the data from disk file and get the name of router*/
+void ripInit(string filename, map<string, struct RouterTab> &table, map<int, string> &adjTab, struct Host &host);
+
+/*convert the router table to string*/
+void ripSend(string &content, map<string, struct RouterTab> &table, struct Host &host);
+
+/*receive the router table from src router and update own table*/
+void ripUpdate(struct Host from, map<string, struct RouterTab> &srcTab, map<string, struct RouterTab> &adjTable, map<string, struct RouterTab> &routeTable, struct Host &host);
+
+/*refresh the route table*/
+void ripRefresh(map<string, struct RouterTab> &bufferdAdj, map<string, struct RouterTab> &newAdj, map<string, struct RouterTab> &table, struct Host &host);
+
+/*receive the socket content and turn it to map*/
+void ripReceive(string content, map<string, struct RouterTab> &srcTab, struct Host &from);
+
+/*print router table*/
+void ripPrintTable(map<string, struct RouterTab> &table, int &printNum, struct Host &host);
+
+
+#endif
diff --git a/socket.cpp b/socket.cpp
new file mode 100644
index 0000000..c03e366
--- /dev/null
+++ b/socket.cpp
@@ -0,0 +1,98 @@
+#include "socket.h"
+#include <string.h>
+#include <stdlib.h>
+#include <arpa/inet.h>
+#include <sys/socket.h>
+#include <stdio.h>
+
+
+using namespace std;
+
+int socketBind(int port)
+{	
+	//create socket
+	int fd = socket(AF_INET, SOCK_DGRAM, 0);
+	if(fd == -1)
+	{
+		perror("creat error\n");
+		return -1;
+	}
+	
+	//printf("create socket, fd: %d\n", fd);
+	
+	//build connection
+	struct sockaddr_in siMe;
+	memset((char *) &siMe, 0, sizeof(siMe));
+	
+	siMe.sin_family = AF_INET;
+	siMe.sin_port = htons(port);
+	siMe.sin_addr.s_addr = inet_addr("127.0.0.1");
+	
+	int r = bind(fd, (struct sockaddr*)&siMe, sizeof(siMe));
+	if(r == -1)
+	{
+		perror("bind error\n");
+		close(fd);
+		return -1;
+	}
+	//printf("bind successfully!\n");
+	return fd;
+	
+}
+
+int socketSend(int fd, int port, string content)
+{
+	//build buffer
+	
+	char *buf = new char[BUFFERSIZE];
+	memset(buf, '\0', BUFFERSIZE);
+	strcpy(buf, content.c_str());
+	
+	//build connection
+	struct sockaddr_in siTo;
+	memset((char *) &siTo, 0, sizeof(siTo));
+	
+	siTo.sin_family = AF_INET;
+	siTo.sin_port = htons(port);
+	siTo.sin_addr.s_addr = inet_addr("127.0.0.1");
+	
+	
+	//printf("socketSend %s\n", buf);
+	
+	//send content
+	int r = sendto(fd, buf, BUFFERSIZE - 1, 0, (struct sockaddr*)&siTo, sizeof(siTo));
+	if(r == -1)
+	{
+		perror("send error\n");
+		return -1;
+	}
+	return 0;
+}
+
+int socketReceive(int fd, string &content)
+{
+	char *buf = new char[BUFFERSIZE];
+	memset(buf, '\0', BUFFERSIZE);
+	
+	//build connection
+	struct sockaddr_in siFrom;
+	memset((char *)&siFrom, 0, sizeof(siFrom));
+	
+	//receive content
+	socklen_t len = sizeof(siFrom);
+	int r = recvfrom(fd, buf, BUFFERSIZE - 1, 0, (struct sockaddr *)&siFrom, &len);
+	
+	if(r > 0)
+	{
+		int port = ntohs(siFrom.sin_port);
+	
+		//read buffer
+		content = string(buf);
+		return port;
+	}
+	//perror("receive error\n");
+	return -1;
+	
+	
+	
+}
diff --git a/socket.h b/socket.h
new file mode 100644
index 0000000..7e7299d
--- /dev/null
+++ b/socket.h
@@ -0,0 +1,17 @@
+#ifndef _SOCKET_H_
+#define _SOCKET_H_
+
+#include <string>
+
+#define BUFFERSIZE 2048
+
+/*bind socket return fd if success*/
+int socketBind(int port);
+
+/*send content to the router on port, return 0 if success*/
+int socketSend(int fd, int port, std::string content);
+
+/*receive content, return port number if success, else return -1*/
+int socketReceive(int fd, std::string &content);
+
+#endif