client登陆openfire，大概总共须要9个来回才完毕登录。
在2G情况下。就表现为client登录特别慢，所以，为解决问题，对openfire进行了例如以下优化
openfire的连接、登陆过程分为几个步骤，完整报文例如以下。总共分为9个round trip：
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1 STREAM
RECV：<stream:stream to="jacklin-pc" xmlns="jabber:client" xmlns:stream="http://etherx.jabber.org/streams" version="1.0">
SENT：<?xml version='1.0' encoding='UTF-8'?><stream:stream xmlns:stream="http://etherx.jabber.org/streams" xmlns="jabber:client" from="jacklin-pc" id="96508a6d" xml:lang="en" version="1.0"> SENT：<stream:features><starttls xmlns="urn:ietf:params:xml:ns:xmpp-tls"></starttls><mechanisms xmlns="urn:ietf:p arams:xml:ns:xmpp-sasl"><mechanism>DIGEST-MD5</mechanism><mechanism>JIVE-SHAREDSECRET</mechanism><mechanism>PLAIN</mechanism><mechanism>ANONYMOUS</mechanism><mechanism>CRAM-MD5</mechanism></mechanisms><compression xmlns="http://jabber.org/features/compress"><method>zlib</method></compression><auth xmlns="http://jabber.org/features/iq-auth"/><register xmlns="http://jabber.org/features/iq-register"/></stream:features>2 TLS
RECV：<starttls xmlns="urn:ietf:params:xml:ns:xmpp-tls"/>
SENT：<proceed xmlns="urn:ietf:params:xml:ns:xmpp-tls"/>
3 STREAM
RECV：<stream:stream to="jacklin-pc" xmlns="jabber:client" xmlns:stream="http://etherx.jabber.org/streams" version="1.0">
SENT：<?
xml version='1.0' encoding='UTF-8'?><stream:stream xmlns:stream="http://etherx.jabber.org/streams" xmlns="jabber:client" from="jacklin-pc" id="96508a6d" xml:lang="en" version="1.0"><stream:features><mechanisms xmlns="urn:ietf:params:xml:ns:xmpp-sasl"><mechanism>DIGEST-MD5</mechanism><mechanism>JIVE-SHAREDSECRET</mechanism><mechanism>PLAIN</mechanism><mechanism>ANONYMOUS</mechanism><mechanism>CRAM-MD5</mechanism></mechanisms><compression xmlns="http://jabber.org/features/compress"><method>zlib</method></compression><auth xmlns="http://jabber.org/features/iq-auth"/><register xmlns="http://jabber.org/features/iq-register"/></stream:features>
4 SASLRECV：<auth mechanism="PLAIN" xmlns="urn:ietf:params:xml:ns:xmpp-sasl">cmVhbG09ImphY2tsaW4tcGMiLG5vbmNlPSJMamw2RGt4Y3hGSDZxb2dTRE55Nmw2VkYreVQ2YjROMFlTa1BBSlZqIixxb3A9ImF1dGgiLGNoYXJzZXQ9dXRmLTgsYWxnb3JpdGhtPW1kNS1zZXNz</auth>
SENT：<success xmlns="urn:ietf:params:xml:ns:xmpp-sasl"></success>
5 STREAMRECV：<stream:stream to="jacklin-pc" xmlns="jabber:client" xmlns:stream="http://etherx.jabber.org/streams" version="1.0">
SENT：<?xml version='1.0' encoding='UTF-8'?><stream:stream xmlns:stream="http://etherx.jabber.org/streams" xmlns="jabber:client" from="jacklin-pc" id="96508a6d" xml:lang="en" version="1.0"><stream:features><compression xmlns="http://jabber.org/features/compress"><method>zlib</method></compression><bind xmlns="urn:ietf:params:xml:ns:xmpp-bind"/><session xmlns="urn:ietf:params:xml:ns:xmpp-session"/></stream:features>
6 BINDRECV：<iq id="SfW08-0" type="set"><bind xmlns="urn:ietf:params:xml:ns:xmpp-bind"><resource>Spark 2.6.3</resource></bind></iq>
SENT：<iq type="result" id="SfW08-0" to="jacklin-pc/96508a6d"><bind xmlns="urn:ietf:params:xml:ns:xmpp-bind"><jid>test001@jacklin-pc/Spark 2.6.3</jid></bind></iq>
7 SESSIONRECV：<iq id="SfW08-1" type="set"><session xmlns="urn:ietf:params:xml:ns:xmpp-session"/></iq>
SENT：<iq type="result" id="SfW08-1" to="test001@jacklin-pc/Spark 2.6.3"/> 8 PRESENCERECV：<presence id="SfW08-6"><status>在线</status><priority>1</priority></presence>
9 ZLIB
RECV：<compress xmlns='http://jabber.org/protocol/compress'><method>zlib</method></compress>
SENT：<compressed xmlns='http://jabber.org/protocol/compress'/>
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1 STREAM优化
当中STREAM类似查询server功能，server会把server的特性返回给client，比如SASL策略，iq-auth，zlib压缩，xmpp-bind等等。事实上，假设是内部定制的系统，这些特性server与client都是共知的，所以不须要查询，全然能够省略这些步骤。
可是，我发现，在client第一次发送stream时，是须要初始化一些内容的。所以，须要再例如以下地方。增加例如以下代码：
org.jivesoftware.openfire.nio.ConnectionHandler
@Override public void sessionOpened(IoSession session) throws Exception { // Create a new XML parser for the new connection. The parser will be // used by the XMPPDecoder filter. final XMLLightweightParser parser = new XMLLightweightParser(CHARSET); session.setAttribute(XML_PARSER, parser); // Create a new NIOConnection for the new session final NIOConnection connection = createNIOConnection(session); session.setAttribute(CONNECTION, connection); session.setAttribute(HANDLER, createStanzaHandler(connection)); // Set the max time a connection can be idle before closing it. This // amount of seconds // is divided in two, as Openfire will ping idle clients first (at 50% // of the max idle time) // before disconnecting them (at 100% of the max idle time). This // prevents Openfire from // removing connections without warning. final int idleTime = getMaxIdleTime() / 2; if (idleTime > 0) { session.setIdleTime(IdleStatus.READER_IDLE, idleTime); } // ADD LOCALSESSION START=========================================================== Log.info("[DO LOCALSESSION]"); int hashCode = Thread.currentThread().hashCode(); XMPPPacketReader parser1 = parsers.get(hashCode); if (parser1 == null) { parser1 = new XMPPPacketReader(); parser1.setXPPFactory(factory); parsers.put(hashCode, parser1); } String msg = " "; StanzaHandler handler = (StanzaHandler) session.getAttribute(HANDLER); try { handler.process(msg, parser1); } catch (Exception e) { Log.error( "Closing connection due to error while processing message: " + msg, e); connection.close(); } // ADD LOCALSESSION END============================================================== } 此目的是让server在client建立连接阶段就初始化client的资源。 2 SESSION
session事实上从server端看，仅仅是回复了一下client，并没有起什么作用，所以client能够不发这段报文，server端不须要修改。server端处理步骤例如以下。
org.jivesoftware.openfire.handler.IQSessionEstablishmentHandler
public class IQSessionEstablishmentHandler extends IQHandler { private IQHandlerInfo info; public IQSessionEstablishmentHandler() { super("Session Establishment handler"); info = new IQHandlerInfo("session", "urn:ietf:params:xml:ns:xmpp-session"); } @Override public IQ handleIQ(IQ packet) throws UnauthorizedException { // Just answer that the session has been activated IQ reply = IQ.createResultIQ(packet); return reply; } @Override public IQHandlerInfo getInfo() { return info; }} 3 BIND,PRESENCE,ZLIB 事实上PRESENCE和ZLIB能够在clientBIND操作之后。server端直接进行，不须要client再次协商。所以。我在下面代码。进行了下面修改：
org.jivesoftware.openfire.handler.IQBindHandler
@Override public IQ handleIQ(IQ packet) throws UnauthorizedException { LocalClientSession session = (LocalClientSession) sessionManager .getSession(packet.getFrom()); // If no session was found then answer an error (if possible) if (session == null) { Log.error("Error during resource binding. Session not found in " + sessionManager.getPreAuthenticatedKeys() + " for key " + packet.getFrom()); // This error packet will probably won't make it through IQ reply = IQ.createResultIQ(packet); reply.setChildElement(packet.getChildElement().createCopy()); reply.setError(PacketError.Condition.internal_server_error); return reply; } IQ reply = IQ.createResultIQ(packet); Element child = reply.setChildElement("bind", "urn:ietf:params:xml:ns:xmpp-bind"); // Check if the client specified a desired resource String resource = packet.getChildElement().elementTextTrim("resource"); if (resource == null || resource.length() == 0) { // None was defined so use the random generated resource resource = session.getAddress().getResource(); } else { // Check that the desired resource is valid try { resource = JID.resourceprep(resource); } catch (StringprepException e) { reply.setChildElement(packet.getChildElement().createCopy()); reply.setError(PacketError.Condition.jid_malformed); // Send the error directly since a route does not exist at this // point. session.process(reply); return null; } } // Get the token that was generated during the SASL authentication AuthToken authToken = session.getAuthToken(); if (authToken == null) { // User must be authenticated before binding a resource reply.setChildElement(packet.getChildElement().createCopy()); reply.setError(PacketError.Condition.not_authorized); // Send the error directly since a route does not exist at this // point. session.process(reply); return reply; } if (authToken.isAnonymous()) { // User used ANONYMOUS SASL so initialize the session as an // anonymous login session.setAnonymousAuth(); } else { String username = authToken.getUsername().toLowerCase(); // If a session already exists with the requested JID, then check to // see // if we should kick it off or refuse the new connection ClientSession oldSession = routingTable.getClientRoute(new JID( username, serverName, resource, true)); if (oldSession != null) { try { int conflictLimit = sessionManager.getConflictKickLimit(); if (conflictLimit == SessionManager.NEVER_KICK) { reply.setChildElement(packet.getChildElement() .createCopy()); reply.setError(PacketError.Condition.conflict); // Send the error directly since a route does not exist // at this point. session.process(reply); return null; } int conflictCount = oldSession.incrementConflictCount(); if (conflictCount > conflictLimit) { // Kick out the old connection that is conflicting with // the new one StreamError error = new StreamError( StreamError.Condition.conflict); oldSession.deliverRawText(error.toXML()); oldSession.close(); } else { reply.setChildElement(packet.getChildElement() .createCopy()); reply.setError(PacketError.Condition.conflict); // Send the error directly since a route does not exist // at this point. session.process(reply); return null; } } catch (Exception e) { Log.error("Error during login", e); } } // If the connection was not refused due to conflict, log the user // in session.setAuthToken(authToken, resource); } child.addElement("jid").setText(session.getAddress().toString()); // Send the response directly since a route does not exist at this // point. session.process(reply); // After the client has been informed, inform all listeners as well. SessionEventDispatcher.dispatchEvent(session, SessionEventDispatcher.EventType.resource_bound); // ADD COMPRESSION START================================================== session.getConnection().addCompression(); session.getConnection().startCompression(); Log.info("[DO COMPRESSION]"); // ADD COMPRESSION END==================================================== // ADD PRESENCE START==================================================== String domain = XMPPServer.getInstance().getServerInfo() .getXMPPDomain(); Presence pp = new Presence(); pp.setFrom(session.getAddress().toString()); // pp.setTo(domain); XMPPServer.getInstance().getPacketRouter().route(pp); Log.info("[DO PRESENCE]:"+ pp.toXML()); // ADD PRESENCE END==================================================== return null; } 经过以上优化之后，server与client的协商仅仅剩下3个round trip。步骤例如以下：
2 TLS
RECV：<starttls xmlns="urn:ietf:params:xml:ns:xmpp-tls"/>SENT：<proceed xmlns="urn:ietf:params:xml:ns:xmpp-tls"/>
4 SASL
RECV：<auth mechanism="PLAIN" xmlns="urn:ietf:params:xml:ns:xmpp-sasl">cmVhbG09ImphY2tsaW4tcGMiLG5vbmNlPSJMamw2RGt4Y3hGSDZxb2dTRE55Nmw2VkYreVQ2YjROMFlTa1BBSlZqIixxb3A9ImF1dGgiLGNoYXJzZXQ9dXRmLTgsYWxnb3JpdGhtPW1kNS1zZXNz</auth>
SENT：<success xmlns="urn:ietf:params:xml:ns:xmpp-sasl"></success>
6 BIND
RECV：<iq id="SfW08-0" type="set"><bind xmlns="urn:ietf:params:xml:ns:xmpp-bind"><resource>Spark 2.6.3</resource></bind></iq>
SENT：<iq type="result" id="SfW08-0" to="jacklin-pc/96508a6d"><bind xmlns="urn:ietf:params:xml:ns:xmpp-bind"><jid>test001@jacklin-pc/Spark 2.6.3</jid></bind></iq>client依照例如以下节奏发送报文。并进行操作就能够了。client改动代码。在这里不做描写叙述，请改动者自行尝试