work commit

src/applications/diameter/DiameterBase.cc

@@ -46,11 +46,11 @@ void DiameterBase::initialize(int stage) {
 
 void DiameterBase::handleMessage(cMessage *msg) {
 
-    if (msg->isSelfMessage()) {
+    if (msg->isSelfMessage()) { // handles timers
         DiameterPeer *peer = (DiameterPeer*)msg->getContextPointer();
         peer->processTimer(msg);
-    } else {
-        DiameterConnection *conn = connMap.findConnectionFor(msg);
+    } else {    // handles SCTP messages
+        DiameterConnection *conn = conns.findConnectionFor(msg);
         if (!conn) {
             // new connection -- create new socket object and server process
         	SCTPSocket *socket = new SCTPSocket(msg);
@@ -58,7 +58,7 @@ void DiameterBase::handleMessage(cMessage *msg) {
             conn = new DiameterConnection(this);
             conn->setType(RESPONDER);
             conn->setSocket(socket);
-            connMap.addConnection(conn);
+            conns.addConnection(conn);
         	socket->setCallbackObject(conn);
         	socket->setOutboundStreams(outboundStreams);
 
@@ -197,7 +197,7 @@ DiameterConnection *DiameterBase::createConnection(AddressVector addresses, int
    	conn->setAddresses(addresses);
    	conn->setPort(port);
    	conn->setType(INITIATOR);
-   	connMap.addConnection(conn);
+   	conns.addConnection(conn);
 
    	return conn;
 }

src/applications/diameter/DiameterBase.h

@@ -22,98 +22,117 @@
 #include <string>
 #include "SCTPSocket.h"
 #include "DiameterConnectionMap.h"
-#include "DiameterSessionTable.h"
+#include "DiameterSession.h"
 #include "DiameterPeerTable.h"
 #include "RoutingTableAccess.h"
 
 /*
- * Implements the SCTP protocol. This section describes the internal
- * architecture of the SCTP model.
+ * Implements the Diameter base protocol. This section describes the internal
+ * architecture of the Diameter model.
  *
- *   You may want to check the SCTPSocket
- * class which makes it easier to use SCTP from applications.
- *
- * The SCTP protocol implementation is composed of several classes (discussion
+ * The Diameter base protocol implementation is composed of several classes (discussion
  * follows below):
- *   - SCTP: the module class
- *   - SCTPAssociation: manages a connection
- *   - SCTPSendQueue, SCTPReceiveQueue: abstract base classes for various types
- *      of send and receive queues
- *   - SCTPAlgorithm: abstract base class for SCTP algorithms
- *
- * SCTP subclassed from cSimpleModule. It manages socketpair-to-connection
- * mapping, and dispatches segments and user commands to the appropriate
- * SCTPAssociation object.
- *
- * SCTPAssociation manages the connection, with the help of other objects.
- * SCTPAssociation itself implements the basic SCTP "machinery": takes care
- * of the state machine, stores the state variables (TCB), sends/receives
- *   etc.
- *
- * SCTPAssociation internally relies on 3 objects. The first two are subclassed
- * from SCTPSendQueue and SCTPReceiveQueue. They manage the actual data stream,
- * so SCTPAssociation itself only works with sequence number variables.
- * This makes it possible to easily accomodate need for various types of
- * simulated data transfer: real byte stream, "virtual" bytes (byte counts
- * only), and sequence of cMessage objects (where every message object is
- * mapped to a SCTP sequence number range).
- *
- * Currently implemented send queue and receive queue classes are
- * SCTPVirtualDataSendQueue and SCTPVirtualDataRcvQueue which implement
- * queues with "virtual" bytes (byte counts only).
+ *   - DiameterBase: the module class
+ *   - DiameterConnection: manages a connection between two peers
+ *   - DiameterPeer: manages a Diameter peer
+ *   - DiameterSession: manages a session between end to end peers
+ *   - DiameterApplication: manages a Diameter application
  *
- * The third object is subclassed from SCTPAlgorithm. Control over
- * retransmissions, congestion control and ACK sending are "outsourced"
- * from SCTPAssociation into SCTPAlgorithm: delayed acks, slow start, fast rexmit,
- * etc. are all implemented in SCTPAlgorithm subclasses.
+ * Diameter base class holds the server socket from which each Diameter connection is forked.
+ * Also it manages the connection table, peer table and session table.
  *
- * The concrete SCTPAlgorithm class to use can be chosen per connection (in OPEN)
- * or in a module parameter.
+ * All Diameter base protocol model is implemented according to RFC 3588.
  */
 class DiameterBase : public cSimpleModule {
-public:
-	std::string fqdn;
-	std::string realm;
-	unsigned vendorId;
-	std::string productName;
-	unsigned sessionIds;
-
 protected:
+    std::string fqdn;
+    std::string realm;
+    unsigned vendorId;
+    std::string productName;
+    unsigned sessionIds;
 	int outboundStreams;
     SCTPSocket serverSocket;
-    DiameterConnectionMap connMap;
+    DiameterConnectionMap conns;
     DiameterSessionTable sessions;
     DiameterPeerTable peers;
     IRoutingTable *rT;
 
+    /*
+     * Methods for loading the configuration from the XML file
+     * ex.
+     *   <DNS>
+     *       <Entry fqdn="mme.lte.test" address="192.168.3.2"/>
+     *   </DNS>
+     *   <Diameter
+     *           fqdn="hss.lte.test"
+     *           realm="lte.test"
+     *           vendor="0"
+     *           product="HSSDiameter">
+     *       <Listeners port="3868">
+     *           <Listener address="192.168.3.1"/>
+     *       </Listeners>
+     *       <Peers>
+     *       </Peers>
+     *   </Diameter>
+     */
     void loadOwnConfigFromXML(const cXMLElement & diameterNode);
     void loadPeersFromXML(const cXMLElement & diameterNode);
     void loadListenersFromXML(const cXMLElement & diameterNode);
     void loadConfigFromXML(const char *filename);
     AddressVector queryDNS(const cXMLElement& diameterNode, const std::string fqdnIn, int port);
     AddressVector findLocalAddresses(AddressVector remoteAddrs);
+
 public:
     DiameterBase();
     virtual ~DiameterBase();
 
     virtual int numInitStages() const  { return 5; }
+
+    /*
+     * Method for reading and processing the configuration file. This includes
+     * loading the Diameter peers, creating for each a initiating or responding
+     * Diameter connection and loading the Diameter application.
+     */
     void initialize(int stage);
+
+    /*
+     * Method for handling incoming messages. If the message is a timer, it sends it
+     * to the appropriate peer. If the message is a SCTP message, it finds the
+     * appropriate socket and sends the message to it. If no socket is available,
+     * it creates a new socket together with a new Diameter connection.
+     */
     void handleMessage(cMessage *msg);
 
     /*
-     *
+     * Method for processing application messages. This method should be overridden
+     * by Diameter application implementations.
      */
     virtual DiameterMessage *processMessage(DiameterMessage *msg) { return NULL; }
 
+    /*
+     * Getter methods.
+     */
     int getOutboundStreams() { return outboundStreams; }
 	SCTPSocket getServerSocket() { return serverSocket; }
+	std::string getFqdn() { return fqdn; }
+	std::string getRealm() { return realm; }
+	unsigned getVendorId() { return vendorId; }
+	std::string getProductName() { return productName; }
 
+	/*
+	 * Utility methods.
+	 */
     DiameterConnection *createConnection(AddressVector addresses, int port);
 	DiameterPeer *createPeer(std::string dFQDN, std::string dRealm, DiameterConnection *conn, DiameterApplication *appl = NULL);
-	DiameterConnection *removeConnection(DiameterConnection *conn) { return connMap.removeConnection(conn); }
-	DiameterPeer *findPeer(std::string dFQDN, std::string dRealm = "") { return peers.findPeer(dFQDN, dRealm); }
-	DiameterPeer *findPeer(unsigned applId) { return peers.findPeer(applId); }
+	DiameterConnection *removeConnection(DiameterConnection *conn) { return conns.removeConnection(conn); }
 	DiameterSession *createSession(bool stType);
+	unsigned genSessionId() { return ++sessionIds; }
+
+	/*
+	 * Wrapper methods.
+	 */
+    DiameterPeer *findPeer(std::string dFQDN, std::string dRealm = "") { return peers.findPeer(dFQDN, dRealm); }
+    DiameterPeer *findPeer(unsigned applId) { return peers.findPeer(applId); }
 };
 
 #endif /* DIAMETERBASE_H_ */

src/applications/diameter/DiameterClient.cc

-//
-// Copyright (C) 2012 Calin Cerchez
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-// 
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Lesser General Public License for more details.
-// 
-// You should have received a copy of the GNU Lesser General Public License
-// along with this program.  If not, see http://www.gnu.org/licenses/.
-// 
-
-#include "DiameterClient.h"
-
-Define_Module(DiameterClient);
-
-DiameterClient::DiameterClient() {
-	// TODO Auto-generated constructor stub
-
-}
-
-DiameterClient::~DiameterClient() {
-	// TODO Auto-generated destructor stub
-}

src/applications/diameter/DiameterClient.h

-//
-// Copyright (C) 2012 Calin Cerchez
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-// 
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Lesser General Public License for more details.
-// 
-// You should have received a copy of the GNU Lesser General Public License
-// along with this program.  If not, see http://www.gnu.org/licenses/.
-// 
-
-#ifndef DIAMETERCLIENT_H_
-#define DIAMETERCLIENT_H_
-
-#include "DiameterBase.h"
-
-class DiameterClient : public DiameterBase {
-public:
-	DiameterClient();
-	virtual ~DiameterClient();
-
-	void initialize(int stage) { DiameterBase::initialize(stage); }
-	void handleMessage(cMessage *msg) { DiameterBase::handleMessage(msg); }
-};
-
-#endif /* DIAMETERCLIENT_H_ */

src/applications/diameter/DiameterClient.ned

-//
-// Copyright (C) 2012 Calin Cerchez
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-// 
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Lesser General Public License for more details.
-// 
-// You should have received a copy of the GNU Lesser General Public License
-// along with this program.  If not, see http://www.gnu.org/licenses/.
-// 
-
-package inet.applications.diameter;
-
-simple DiameterClient like DiameterBase {
-    parameters:
-        @display("i=block/app");
-        string configFile;
-   	gates:
-        input sctpIn;
-        output sctpOut;
-}
\ No newline at end of file

src/applications/diameter/DiameterServer.cc

-//
-// Copyright (C) 2012 Calin Cerchez
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-// 
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Lesser General Public License for more details.
-// 
-// You should have received a copy of the GNU Lesser General Public License
-// along with this program.  If not, see http://www.gnu.org/licenses/.
-// 
-
-#include "DiameterServer.h"
-
-Define_Module(DiameterServer)
-
-DiameterServer::DiameterServer() {
-	// TODO Auto-generated constructor stub
-
-}
-
-DiameterServer::~DiameterServer() {
-	// TODO Auto-generated destructor stub
-}

src/applications/diameter/DiameterServer.h

-//
-// Copyright (C) 2012 Calin Cerchez
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-// 
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Lesser General Public License for more details.
-// 
-// You should have received a copy of the GNU Lesser General Public License
-// along with this program.  If not, see http://www.gnu.org/licenses/.
-// 
-
-#ifndef DIAMETERSERVER_H_
-#define DIAMETERSERVER_H_
-
-#include "DiameterBase.h"
-
-class DiameterServer : public DiameterBase {
-public:
-	DiameterServer();
-	virtual ~DiameterServer();
-
-	void initialize(int stage) { DiameterBase::initialize(stage); }
-	void handleMessage(cMessage *msg) { DiameterBase::handleMessage(msg); }
-};
-
-#endif /* DIAMETERSERVER_H_ */

src/applications/diameter/DiameterServer.ned

-//
-// Copyright (C) 2012 Calin Cerchez
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-// 
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Lesser General Public License for more details.
-// 
-// You should have received a copy of the GNU Lesser General Public License
-// along with this program.  If not, see http://www.gnu.org/licenses/.
-// 
-
-package inet.applications.diameter;
-
-simple DiameterServer like DiameterBase {
-    parameters:
-        @display("i=block/app");
-        string configFile;
-   	gates:
-        input sctpIn;
-        output sctpOut;
-}
\ No newline at end of file

src/applications/diameter/session/DiameterSession.cc → src/applications/diameter/DiameterSession.cc

@@ -27,8 +27,8 @@ DiameterSession::DiameterSession(DiameterBase *module, bool state) {
 	char time[10];
 	sprintf(time, "%d", (unsigned)simTime().raw());
 	char id[10];
-	sprintf(id, "%d", module->sessionIds++);
-	this->id = module->fqdn + ";" + time + ";" + id;
+	sprintf(id, "%d", module->genSessionId());
+	this->id = module->getFqdn() + ";" + time + ";" + id;
 
 	fsm = new cFSM();
 	fsm->setName("sessionState");
@@ -119,3 +119,30 @@ const char *DiameterSession::eventName(int event) {
     return s;
 #undef CASE
 }
+
+DiameterSessionTable::DiameterSessionTable() {
+    // TODO Auto-generated constructor stub
+
+}
+
+DiameterSessionTable::~DiameterSessionTable() {
+    // TODO Auto-generated destructor stub
+}
+
+DiameterSession *DiameterSessionTable::find(std::string id) {
+    for (unsigned i = 0; i < sessions.size(); i++) {
+        if (sessions.at(i)->getId() == id)
+            return sessions.at(i);
+    }
+    return NULL;
+}
+
+void DiameterSessionTable::erase(unsigned start, unsigned end) {
+    SessionTable::iterator first = sessions.begin() + start;
+    SessionTable::iterator last = sessions.begin() + end;
+    SessionTable::iterator i = first;
+    for (;i != last; ++i)
+        delete *i;
+    sessions.erase(first, last);
+}
+

src/applications/diameter/session/DiameterSession.h → src/applications/diameter/DiameterSession.h

@@ -41,9 +41,14 @@ enum SessionEvent {
 	RequestReceived,
 };
 
+/*
+ * Class Diameter session. The class implements the session state machine
+ * and processes Diameter application messages which are not meant for
+ * Diameter base protocol.
+ */
 class DiameterSession : public cPolymorphic {
 private:
-	bool state;
+	bool type;  // stateful or stateless
 	std::string id;
 	cFSM *fsm;
 //	cMessage *sTimer;
@@ -62,4 +67,20 @@ public:
 	void performStateTransition(SessionEvent &event, unsigned applId, DiameterPeer *peer, DiameterMessage *msg);
 };
 
+class DiameterSessionTable {
+private:
+    typedef std::vector<DiameterSession*> SessionTable;
+    SessionTable sessions;
+public:
+    DiameterSessionTable();
+    virtual ~DiameterSessionTable();
+
+    DiameterSession *find(std::string id);
+    DiameterSession *at(unsigned i) { return sessions.at(i); }
+    void push_back(DiameterSession *session) { sessions.push_back(session); }
+    void erase(unsigned start, unsigned end);
+    unsigned size() {return sessions.size();}
+//  void deleteSessions();
+};
+
 #endif /* DIAMETERSESSION_H_ */

src/applications/diameter/peer/DiameterPeer.cc

@@ -29,8 +29,8 @@ DiameterPeer::DiameterPeer(DiameterBase *module) {
 	this->module = module;
 	this->dFQDN = "";
 	this->dFQDN = "";
-	this->oFQDN = module->fqdn;
-	this->oRealm = module->realm;
+	this->oFQDN = module->getFqdn();
+	this->oRealm = module->getRealm();
 
 	char fsmname[24];
 	sprintf(fsmname, "fsm-%s", oFQDN.data());
@@ -464,8 +464,8 @@ void DiameterPeer::sendCER(DiameterConnection *conn) {
 	cer->setHdr(DiameterUtils().createHeader(CapabilitiesExchange, 1, 0, 0, 0, appl->applId, uniform(0, 10000), uniform(0, 10000)));
 
 	cer->pushAvp(DiameterUtils().createAddressAVP(AVP_HostIPAddress, 0, 1, 0, 0, module->getServerSocket().getLocalAddresses().at(0)));
-	cer->pushAvp(DiameterUtils().createUnsigned32AVP(AVP_VendorId, 0, 1, 0, 0, module->vendorId));
-	cer->pushAvp(DiameterUtils().createUTF8StringAVP(AVP_ProductName, 0, 1, 0, 0, module->productName));
+	cer->pushAvp(DiameterUtils().createUnsigned32AVP(AVP_VendorId, 0, 1, 0, 0, module->getVendorId()));
+	cer->pushAvp(DiameterUtils().createUTF8StringAVP(AVP_ProductName, 0, 1, 0, 0, module->getProductName()));
 
 	if (appl) {
 		AVP *authApplId = DiameterUtils().createUnsigned32AVP(AVP_AuthApplId, 0, 1, 0, 0, appl->applId);
@@ -486,8 +486,8 @@ void DiameterPeer::sendCEA(DiameterConnection *conn, DiameterMessage *cer, unsig
 
 	cea->pushAvp(DiameterUtils().createUnsigned32AVP(AVP_ResultCode, 0, 1, 0, 0, resCode));
 	cea->pushAvp(DiameterUtils().createAddressAVP(AVP_HostIPAddress, 0, 1, 0, 0, module->getServerSocket().getLocalAddresses().at(0)));
-	cea->pushAvp(DiameterUtils().createUnsigned32AVP(AVP_VendorId, 0, 1, 0, 0, module->vendorId));
-	cea->pushAvp(DiameterUtils().createUTF8StringAVP(AVP_ProductName, 0, 1, 0, 0, module->productName));
+	cea->pushAvp(DiameterUtils().createUnsigned32AVP(AVP_VendorId, 0, 1, 0, 0, module->getVendorId()));
+	cea->pushAvp(DiameterUtils().createUTF8StringAVP(AVP_ProductName, 0, 1, 0, 0, module->getProductName()));
 
 	if (appl) {
 		std::vector<AVP*> avps;

src/applications/diameter/session/DiameterSessionTable.cc

-//
-// Copyright (C) 2012 Calin Cerchez
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-// 
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Lesser General Public License for more details.
-// 
-// You should have received a copy of the GNU Lesser General Public License
-// along with this program.  If not, see http://www.gnu.org/licenses/.
-// 
-
-#include "DiameterSessionTable.h"
-#include <algorithm>
-
-DiameterSessionTable::DiameterSessionTable() {
-	// TODO Auto-generated constructor stub
-
-}
-
-DiameterSessionTable::~DiameterSessionTable() {
-	// TODO Auto-generated destructor stub
-}
-
-DiameterSession *DiameterSessionTable::find(std::string id) {
-	for (unsigned i = 0; i < sessions.size(); i++) {
-		if (sessions.at(i)->getId() == id)
-			return sessions.at(i);
-	}
-	return NULL;
-}
-
-void DiameterSessionTable::erase(unsigned start, unsigned end) {
-	SessionTable::iterator first = sessions.begin() + start;
-	SessionTable::iterator last = sessions.begin() + end;
-	SessionTable::iterator i = first;
-	for (;i != last; ++i)
-		delete *i;
-	sessions.erase(first, last);
-}

src/applications/diameter/session/DiameterSessionTable.h

-//
-// Copyright (C) 2012 Calin Cerchez
-//
-// This program is free software: you can redistribute it and/or modify
-// it under the terms of the GNU Lesser General Public License as published by
-// the Free Software Foundation, either version 3 of the License, or
-// (at your option) any later version.
-// 
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-// GNU Lesser General Public License for more details.
-// 
-// You should have received a copy of the GNU Lesser General Public License
-// along with this program.  If not, see http://www.gnu.org/licenses/.
-// 
-
-#ifndef DIAMETERSESSIONTABLE_H_
-#define DIAMETERSESSIONTABLE_H_
-
-#include "DiameterSession.h"
-
-class DiameterSessionTable {
-private:
-	typedef std::vector<DiameterSession*> SessionTable;
-	SessionTable sessions;
-public:
-	DiameterSessionTable();
-	virtual ~DiameterSessionTable();
-
-	DiameterSession *find(std::string id);
-	DiameterSession *at(unsigned i) { return sessions.at(i); }
-	void push_back(DiameterSession *session) { sessions.push_back(session); }
-	void erase(unsigned start, unsigned end);
-	unsigned size() {return sessions.size();}
-//	void deleteSessions();
-};
-
-#endif /* DIAMETERSESSIONTABLE_H_ */

src/applications/diameter/utils/DiameterMessage.h

@@ -21,6 +21,10 @@
 #include "INETDefs.h"
 #include "DiameterMessage_m.h"
 
+/*
+ * Class for Diameter message. This class inherits the message
+ * base class from .msg file and adds the vector with the AVPs.
+ */
 class DiameterMessage : public DiameterMessage_Base {
 protected:
 	typedef std::vector<AVPPtr> AVPVector;
@@ -29,17 +33,42 @@ public:
 	DiameterMessage(const char *name=NULL, int kind=0) : DiameterMessage_Base(name,kind) {}
 	DiameterMessage(const DiameterMessage& other) : DiameterMessage_Base(other.getName()) {operator=(other);}
 	virtual ~DiameterMessage();
+
 	DiameterMessage& operator=(const DiameterMessage& other);
 	virtual DiameterMessage *dup() const {return new DiameterMessage(*this);}
 
+	/*
+	 * Methods overridden but not used. You should use instead pushAvp or insertAvp.
+	 */
     virtual void setAvpsArraySize(unsigned int size);
     virtual void setAvps(unsigned int k, const AVPPtr& avps_var);
+
+    /*
+     * Getter methods.
+     */
     virtual unsigned int getAvpsArraySize() const;
     virtual AVPPtr& getAvps(unsigned int k);
 
+    /*
+     * Method for pushing AVP at the end of the vector.
+     */
 	void pushAvp(AVPPtr avp) { avps.push_back(avp); }
+
+	/*
+	 * Method for inserting AVP at a given position in the vector.
+	 */
 	void insertAvp(unsigned pos, AVPPtr avp);
+
+	/*
+	 * Method for printing the message contents. Currently it prints info
+	 * only for the header.
+	 */
 	void print();
+
+	/*
+	 * Method for finding a AVP with a given AVP code within the vector.
+	 * It returns NULL if the AVP is not found.
+	 */
 	AVPPtr findAvp(unsigned avpCode);
 };
 

src/applications/diameter/utils/DiameterSerializer.h

@@ -21,17 +21,40 @@
 #include "DiameterMessage.h"
 #include "SCTPMessage_m.h"
 
+/*
+ * Class for serializing and parsing of Diameter messages.
+ * This class will be used to serialize a Diameter message before sending it
+ * to SCTP layer and parsing the message when it comes from SCTP layer.
+ */
 class DiameterSerializer {
 private:
+    /*
+     * Method returns the length of the Diameter message. The length includes
+     * the header, all the AVPs (header + payload) and offset bytes, if it is
+     * needed.
+     */
 	unsigned getMessageLength(DiameterMessage *msg);
+
+	/*
+	 * Methods for serializing and parsing of Diameter header.
+	 */
 	unsigned serializeHeader(DiameterHeader hdr, unsigned len, char *p);
 	unsigned parseHeader(DiameterHeader *hdr, char *p);
 public:
 	DiameterSerializer();
 	virtual ~DiameterSerializer();
 
+	/*
+	 * Methods for serializing and parsing of Diameter AVP.
+	 */
 	unsigned serializeAVP(AVP *avp, char *p);
 	unsigned parseAVP(AVP *avp, char *p);
+
+	/*
+	 * Methods for serializing and parsing of Diameter Message. Serialize method
+	 * will generate directly a SCTP message with the resulted bytes and parse
+	 * method will process a SCTP message and generate the appropriate Diameter message.
+	 */
     SCTPSimpleMessage *serialize(DiameterMessage *msg);
     DiameterMessage *parse(const SCTPSimpleMessage *msg);
 };

src/applications/diameter/utils/DiameterUtils.h

@@ -22,25 +22,31 @@
 #include "DiameterMessage_m.h"
 
 #define IPV4_ADDRESS_TYPE	1
-
 #define IPV4_ADDRESS_SIZE	4
 
+/*
+ * Diameter utility class. It is used for creating and processing Diameter header and AVPs.
+ */
 class DiameterUtils {
-private:
-	AVP *createBaseAVP(unsigned avpCode, bool vendFlag, bool manFlag, bool privFlag, unsigned vendorId);
-
 public:
 	DiameterUtils();
 	virtual ~DiameterUtils();
 
+	/*
+	 * Methods for Diameter header and AVP creation.
+	 */
+    DiameterHeader createHeader(unsigned commandCode, bool reqFlag, bool prxyFlag, bool errFlag, bool retrFlag, unsigned applId, unsigned hopByHopId, unsigned endToEndId);
+	AVP *createBaseAVP(unsigned avpCode, bool vendFlag, bool manFlag, bool privFlag, unsigned vendorId);
 	AVP *createOctetStringAVP(unsigned avpCode, bool vendFlag, bool manFlag, bool privFlag, unsigned vendorId, unsigned len, const char *str);
 	AVP *createUTF8StringAVP(unsigned avpCode, bool vendFlag, bool manFlag, bool privFlag, unsigned vendorId, std::string str);
 	AVP *createAddressAVP(unsigned avpCode, bool vendFlag, bool manFlag, bool privFlag, unsigned vendorId, IPvXAddress addr);
 	AVP *createUnsigned32AVP(unsigned avpCode, bool vendFlag, bool manFlag, bool privFlag, unsigned vendorId, unsigned val);
 	AVP *createInteger32AVP(unsigned avpCode, bool vendFlag, bool manFlag, bool privFlag, unsigned vendorId, int val);
 	AVP *createGroupedAVP(unsigned avpCode, bool vendFlag, bool manFlag, bool privFlag, unsigned vendorId, std::vector<AVP*> avps);
-	DiameterHeader createHeader(unsigned commandCode, bool reqFlag, bool prxyFlag, bool errFlag, bool retrFlag, unsigned applId, unsigned hopByHopId, unsigned endToEndId);
 
+	/*
+	 * Methods for Diameter header and AVP processing.
+	 */
 	unsigned processUnsigned32AVP(AVP *unsigned32AVP);
 	int processInteger32AVP(AVP *integer32AVP);
 	char *processOctetStringAVP(AVP *octetStringAVP);
@@ -48,10 +54,20 @@ public:
 	IPvXAddress processAddressAVP(AVP *addressAVP);
 	std::vector<AVP*> processGroupedAVP(AVP *groupedAVP);
 
+	/*
+	 * Methods for finding AVP or arrays of AVPs in grouped AVPs.
+	 */
 	AVP *findAVP(unsigned avpCode, std::vector<AVP*>avps);
 	std::vector<AVP*> findAVPs(unsigned avpCode, std::vector<AVP*>avps);
 
+	/*
+	 * Method for printing the name of a AVP code.
+	 */
 	const char *avpName(unsigned avpCode);
+
+	/*
+	 * Method for cleaning grouped AVPs.
+	 */
 	void deleteGroupedAVP(std::vector<AVP*>avps);
 };