Re: [twsocket] Multicast question
Il 26/05/2011 15:28, Éric Fleming Bonilha ha scritto:
Hi Emanuele,
Thanks for the examples
I actually have a working application with multicast, but I was
wondering if it was correct, because I tested it with a switch that
manages IGMP and no multicast groups were being created.
I saw that you set TTL to 32, why? The default 1 would not work? I know
that 1 would work just on local network (My case)
I used multicast on wan. Our customer wanted this setting.
What I´m confused is with the group creation, how my ICS based
application with create a multicast group that is visible for switches
(By using IGMP) and switches can manage this multicast distribution?
Without that, multicast would be just like broadcast.
Using wireshark, when a multicast socket enter in listening state, you
should see igmp packets on the net.
These packets should tell to the switch how to manage multicast
distribution.
I saw on TWSocket source that when I start listening it actually sets
the socket to ADD_MEMBERSHIP tp the group, this may be OK for receiving
data, but I´m confused about sending multicast data, because the sender
is the one that was supposed to create the multicast group right? But to
send multicast data on network I need to use Connect method instead of
Listen from the TWSocket, in this case, on Connect method I didn´t find
a mention to ADD_MEMBERSHIP or creating a multicast group.
In my implementation, I start listening also for the sender, using
TUDP.SetTx and TUDP.StartRx methods. I use TUDP.Connect method, only for
send udp unicast packets.
I'm not a multicast expert. I found this kind of solution that worked in
my scenario.
Using my implementation, what kind of packet distribution do you get?
Broadcast?
Bye
Thanks
Eric
-Mensagem Original- From: emanuele bizzarri
Sent: Thursday, May 26, 2011 3:41 AM
To: twsocket@elists.org
Subject: Re: [twsocket] Multicast question
Hi,
this is an example of TUDP class that can be used in multicast (receive
and transmit).
This unit depends by other units, but you can easily extract what you need.
Note that I set multicast ttl.
I hope it will be usefull for you,
Bye
Emanuele
unit ewPlatform_UDP;
interface
uses
ewPlatform_Lists,
ewPlatform_Logger,
ewPlatform_Memory,
ewPlatform_Packets,
ewPlatform_Strings,
OverByteIcsWsocket,
WinSock,
Windows,
SysUtils,
Classes;
type
TOnUDPError=procedure(aError:integer)of object;
TOnUDPDataSent=procedure(aInteger:integer)of object;
TOnUDPDataAvailable=procedure(aSender:TObject;aData:pointer;aSize:integer;aPeerIP:string;aPeerPort:integer)
of object;
TUDP=class
protected
fWS:TWSocket;
fSent:boolean;
fPeerSrc:TSockAddr;
fPeerSrcLen:integer;
fRxData:pointer;
fRxSize:integer;
fWhiteList:TStringList;
fBlackList:TStringList;
fTxList:TStringList;
procedure DataAvailable(aSender:TObject;aError:word);
procedure DataSent(aSender:TObject;aErrCode:word);
procedure DnsLookupDone(aSender:TObject;aErrCode:word);
procedure ChangeState(aSender:TObject;aOldState,aNewState:TSocketState);
procedure Send;
function GetStarted:boolean;
public
pLocalIP:string;
pLocalPort:integer;
pPeerIP:string;
pPeerPort:integer;
pMultiThreaded:boolean;
pMulticast:boolean;
pUseWhiteList:boolean;
pUseBlackList:boolean;
pMulticastTTL:integer;
pGetPeerByData:boolean;
pOnDataSent:TOnUDPDataSent;
pOnDataAvailable:TOnUDPDataAvailable;
pOnError:TOnUDPError;
pOnChangeState:TChangeState;
constructor Create;
destructor Destroy;override;
procedure StartRx;
procedure SetTx;
procedure Disconnect;
procedure Connect;
function Add2WhiteList(aIPPort:string):boolean;
function Add2BlackList(aIPPort:string):boolean;
procedure DeleteFromWhiteList(aIPPort:string);
procedure DeleteFromBlackList(aIPPort:string);
procedure ClearWhiteList;
procedure ClearBlackList;
function NewData(aData:pointer;aSize:integer):integer;
property pStarted:boolean read GetStarted;
end;
implementation
//--
//TUDP
//--
constructor TUDP.Create;
begin
inherited Create;
TLogger.Log('UDP socket creation
threadID='+inttostr(GetCurrentThreadID),lsVerbose,true);
fWS:=TWSocket.Create(nil);
fWS.OnDataAvailable:=DataAvailable;
fWS.OnDataSent:=DataSent;
fWS.OnDnsLookupDone:=DnsLookUpDone;
fWS.OnChangeState:=ChangeState;
fWS.Proto:='udp';
pGetPeerByData:=false;
fTxList:=TStringList.Create;
fSent:=false;
pLocalIP:='0.0.0.0';
pLocalPort:=0;
pPeerIP:='';
pPeerPort:=0;
pMultiThreaded:=false;
pMulticast:=false;
pMulticastTTL:=32;
fWhiteList:=TStringList.Create;
fBlackList:=TStringList.Create;
pUseWhiteList:=false;
pUseBlackList:=false
Re: [twsocket] Multicast question
Hi Emanuele Thanks again for the code, now I understand better the concept of IGMP groups I used multicast on wan. Our customer wanted this setting. I see, I will leave an option for my software for the user to configure the TTL, I´m using default 1 (LAN only) Using wireshark, when a multicast socket enter in listening state, you should see igmp packets on the net. These packets should tell to the switch how to manage multicast distribution. On my implementation, I was using Connect instead of Listen for the sender, so, the sender was not joining the IGMP group, but as I read, the sender is not required to join an IGMP group just the receivers must join the group in order to receive multicast data Using my implementation, what kind of packet distribution do you get? Broadcast? I actually get Multicast distribution but since I don´t have a managed switch over here (that can manage IGMP groups) it works like broadcast, all machines on the network receive the multicast data (If I setup wireshark on them I can see) not only the machines who joined the group, because this is managed by the switch by using IGMP Snooping Now I have a clearer idea of IGMP, but I would like to know if the sender is advised to join the IGMP group, or I can have the sender without joining the group Thanks Eric -- To unsubscribe or change your settings for TWSocket mailing list please goto http://lists.elists.org/cgi-bin/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
Re: [twsocket] Multicast question
Hi,
this is an example of TUDP class that can be used in multicast (receive
and transmit).
This unit depends by other units, but you can easily extract what you need.
Note that I set multicast ttl.
I hope it will be usefull for you,
Bye
Emanuele
unit ewPlatform_UDP;
interface
uses
ewPlatform_Lists,
ewPlatform_Logger,
ewPlatform_Memory,
ewPlatform_Packets,
ewPlatform_Strings,
OverByteIcsWsocket,
WinSock,
Windows,
SysUtils,
Classes;
type
TOnUDPError=procedure(aError:integer)of object;
TOnUDPDataSent=procedure(aInteger:integer)of object;
TOnUDPDataAvailable=procedure(aSender:TObject;aData:pointer;aSize:integer;aPeerIP:string;aPeerPort:integer)
of object;
TUDP=class
protected
fWS:TWSocket;
fSent:boolean;
fPeerSrc:TSockAddr;
fPeerSrcLen:integer;
fRxData:pointer;
fRxSize:integer;
fWhiteList:TStringList;
fBlackList:TStringList;
fTxList:TStringList;
procedure DataAvailable(aSender:TObject;aError:word);
procedure DataSent(aSender:TObject;aErrCode:word);
procedure DnsLookupDone(aSender:TObject;aErrCode:word);
procedure ChangeState(aSender:TObject;aOldState,aNewState:TSocketState);
procedure Send;
function GetStarted:boolean;
public
pLocalIP:string;
pLocalPort:integer;
pPeerIP:string;
pPeerPort:integer;
pMultiThreaded:boolean;
pMulticast:boolean;
pUseWhiteList:boolean;
pUseBlackList:boolean;
pMulticastTTL:integer;
pGetPeerByData:boolean;
pOnDataSent:TOnUDPDataSent;
pOnDataAvailable:TOnUDPDataAvailable;
pOnError:TOnUDPError;
pOnChangeState:TChangeState;
constructor Create;
destructor Destroy;override;
procedure StartRx;
procedure SetTx;
procedure Disconnect;
procedure Connect;
function Add2WhiteList(aIPPort:string):boolean;
function Add2BlackList(aIPPort:string):boolean;
procedure DeleteFromWhiteList(aIPPort:string);
procedure DeleteFromBlackList(aIPPort:string);
procedure ClearWhiteList;
procedure ClearBlackList;
function NewData(aData:pointer;aSize:integer):integer;
property pStarted:boolean read GetStarted;
end;
implementation
//--
//TUDP
//--
constructor TUDP.Create;
begin
inherited Create;
TLogger.Log('UDP socket creation
threadID='+inttostr(GetCurrentThreadID),lsVerbose,true);
fWS:=TWSocket.Create(nil);
fWS.OnDataAvailable:=DataAvailable;
fWS.OnDataSent:=DataSent;
fWS.OnDnsLookupDone:=DnsLookUpDone;
fWS.OnChangeState:=ChangeState;
fWS.Proto:='udp';
pGetPeerByData:=false;
fTxList:=TStringList.Create;
fSent:=false;
pLocalIP:='0.0.0.0';
pLocalPort:=0;
pPeerIP:='';
pPeerPort:=0;
pMultiThreaded:=false;
pMulticast:=false;
pMulticastTTL:=32;
fWhiteList:=TStringList.Create;
fBlackList:=TStringList.Create;
pUseWhiteList:=false;
pUseBlackList:=false;
fRxSize:=256*1024;
getmem(fRxData,fRxSize);
fPeerSrcLen:=sizeof(fPeerSrc);
end;
destructor TUDP.Destroy;
begin
Disconnect;
FreeObjAndNil(fWS);
FreeMemAndNil(fRxData);
FreeObjAndNil(fWhiteList);
FreeObjAndNil(fBlackList);
FreeList(fTxList);
FreeObjAndNil(fTxList);
inherited Destroy;
end;
procedure TUDP.StartRx;
begin
Disconnect;
pLocalIP:=trim(pLocalIP);
if (pLocalIP'')and(pLocalPort0) then
begin
fWS.Proto:='udp';
fWS.MultiThreaded:=pMultiThreaded;
fWS.Addr:=pLocalIP;
fWS.Port:=inttostr(pLocalPort);
if fWS.Addr='' then
fWS.Addr:='0.0.0.0';
if pMulticast then
begin
fWS.MultiCast:=true;
fWS.ReuseAddr:=true;
fWS.MultiCastAddrStr:=pPeerIP;
end;
fWS.Listen;
fWS.SocketRcvBufSize:=fRXSize;
if pMulticast then
setsockopt(fWS.HSocket,IPPROTO_IP,IP_MULTICAST_TTL,@pMulticastTTL,sizeof(pMulticastTTL));
end
else
TLogger.Log('UDP socket start rx error LocalIP='+pLocalIP+'
LocalPort='+inttostr(pLocalPort),lsError,true);
end;
function TUDP.GetStarted:boolean;
begin
result:=false;
if (assigned(fWS)) then
result:=(fWS.State=wsListening)or(fWS.State=wsConnected);
end;
procedure TUDP.SetTx;
var
lRes:boolean;
begin
pPeerIP:=trim(pPeerIP);
lRes:=(pPeerIp'')and(pPeerPort0);
TLogger.Log('UDP socket set tx PeerIP='+pPeerIP+'
PeerPort='+inttostr(pPeerPort)+'...
'+Boolean2Str(lRes,'ok','ko'),Boolean2Severity(lRes,lsVerbose,lsError),true);
fPeerSrc.sin_family:=AF_INET;
fPeerSrc.sin_addr.s_addr:=WSocket_inet_addr(AnsiString(pPeerIP));
fPeerSrc.sin_port:=htons(word(pPeerPort));
fSent:=false;
FreeList(fTxList);
end;
procedure TUDP.Disconnect;
begin
fWS.Shutdown(SD_BOTH);
fWS.Close;
FreeList(fTxList);
fSent:=false;
end;
procedure TUDP.Connect;
begin
Disconnect;
fWS.Proto:='udp';
fWS.MultiThreaded:=pMultiThreaded;
fWS.LocalAddr:=pLocalIP;
fWS.Addr:=trim(pPeerIP);
fWS.Port:=inttostr(pPeerPort);
SetTx;
if (fWS.Addr'')and(pPeerPort0) then
Re: [twsocket] Multicast question
Hi Emanuele,
Thanks for the examples
I actually have a working application with multicast, but I was wondering if
it was correct, because I tested it with a switch that manages IGMP and no
multicast groups were being created.
I saw that you set TTL to 32, why? The default 1 would not work? I know that
1 would work just on local network (My case)
What I´m confused is with the group creation, how my ICS based application
with create a multicast group that is visible for switches (By using IGMP)
and switches can manage this multicast distribution? Without that, multicast
would be just like broadcast.
I saw on TWSocket source that when I start listening it actually sets the
socket to ADD_MEMBERSHIP tp the group, this may be OK for receiving data,
but I´m confused about sending multicast data, because the sender is the one
that was supposed to create the multicast group right? But to send multicast
data on network I need to use Connect method instead of Listen from the
TWSocket, in this case, on Connect method I didn´t find a mention to
ADD_MEMBERSHIP or creating a multicast group.
Thanks
Eric
-Mensagem Original-
From: emanuele bizzarri
Sent: Thursday, May 26, 2011 3:41 AM
To: twsocket@elists.org
Subject: Re: [twsocket] Multicast question
Hi,
this is an example of TUDP class that can be used in multicast (receive
and transmit).
This unit depends by other units, but you can easily extract what you need.
Note that I set multicast ttl.
I hope it will be usefull for you,
Bye
Emanuele
unit ewPlatform_UDP;
interface
uses
ewPlatform_Lists,
ewPlatform_Logger,
ewPlatform_Memory,
ewPlatform_Packets,
ewPlatform_Strings,
OverByteIcsWsocket,
WinSock,
Windows,
SysUtils,
Classes;
type
TOnUDPError=procedure(aError:integer)of object;
TOnUDPDataSent=procedure(aInteger:integer)of object;
TOnUDPDataAvailable=procedure(aSender:TObject;aData:pointer;aSize:integer;aPeerIP:string;aPeerPort:integer)
of object;
TUDP=class
protected
fWS:TWSocket;
fSent:boolean;
fPeerSrc:TSockAddr;
fPeerSrcLen:integer;
fRxData:pointer;
fRxSize:integer;
fWhiteList:TStringList;
fBlackList:TStringList;
fTxList:TStringList;
procedure DataAvailable(aSender:TObject;aError:word);
procedure DataSent(aSender:TObject;aErrCode:word);
procedure DnsLookupDone(aSender:TObject;aErrCode:word);
procedure ChangeState(aSender:TObject;aOldState,aNewState:TSocketState);
procedure Send;
function GetStarted:boolean;
public
pLocalIP:string;
pLocalPort:integer;
pPeerIP:string;
pPeerPort:integer;
pMultiThreaded:boolean;
pMulticast:boolean;
pUseWhiteList:boolean;
pUseBlackList:boolean;
pMulticastTTL:integer;
pGetPeerByData:boolean;
pOnDataSent:TOnUDPDataSent;
pOnDataAvailable:TOnUDPDataAvailable;
pOnError:TOnUDPError;
pOnChangeState:TChangeState;
constructor Create;
destructor Destroy;override;
procedure StartRx;
procedure SetTx;
procedure Disconnect;
procedure Connect;
function Add2WhiteList(aIPPort:string):boolean;
function Add2BlackList(aIPPort:string):boolean;
procedure DeleteFromWhiteList(aIPPort:string);
procedure DeleteFromBlackList(aIPPort:string);
procedure ClearWhiteList;
procedure ClearBlackList;
function NewData(aData:pointer;aSize:integer):integer;
property pStarted:boolean read GetStarted;
end;
implementation
//--
//TUDP
//--
constructor TUDP.Create;
begin
inherited Create;
TLogger.Log('UDP socket creation
threadID='+inttostr(GetCurrentThreadID),lsVerbose,true);
fWS:=TWSocket.Create(nil);
fWS.OnDataAvailable:=DataAvailable;
fWS.OnDataSent:=DataSent;
fWS.OnDnsLookupDone:=DnsLookUpDone;
fWS.OnChangeState:=ChangeState;
fWS.Proto:='udp';
pGetPeerByData:=false;
fTxList:=TStringList.Create;
fSent:=false;
pLocalIP:='0.0.0.0';
pLocalPort:=0;
pPeerIP:='';
pPeerPort:=0;
pMultiThreaded:=false;
pMulticast:=false;
pMulticastTTL:=32;
fWhiteList:=TStringList.Create;
fBlackList:=TStringList.Create;
pUseWhiteList:=false;
pUseBlackList:=false;
fRxSize:=256*1024;
getmem(fRxData,fRxSize);
fPeerSrcLen:=sizeof(fPeerSrc);
end;
destructor TUDP.Destroy;
begin
Disconnect;
FreeObjAndNil(fWS);
FreeMemAndNil(fRxData);
FreeObjAndNil(fWhiteList);
FreeObjAndNil(fBlackList);
FreeList(fTxList);
FreeObjAndNil(fTxList);
inherited Destroy;
end;
procedure TUDP.StartRx;
begin
Disconnect;
pLocalIP:=trim(pLocalIP);
if (pLocalIP'')and(pLocalPort0) then
begin
fWS.Proto:='udp';
fWS.MultiThreaded:=pMultiThreaded;
fWS.Addr:=pLocalIP;
fWS.Port:=inttostr(pLocalPort);
if fWS.Addr='' then
fWS.Addr:='0.0.0.0';
if pMulticast then
begin
fWS.MultiCast:=true;
fWS.ReuseAddr:=true;
fWS.MultiCastAddrStr:=pPeerIP;
end;
fWS.Listen;
fWS.SocketRcvBufSize:=fRXSize;
if pMulticast
[twsocket] Multicast question
Hi I´m wondering how to use ICS properly to send and receive Multicast data. Where can I find example for multicast and ICS? I´m in doubt about the IGMP protocol, do I need to implement anything on application layer or does IGMP protocol is implemented on underlying stack automatically? How my application will create a multicast group on network and/or join a group? Thank you very much! Eric -- To unsubscribe or change your settings for TWSocket mailing list please goto http://lists.elists.org/cgi-bin/mailman/listinfo/twsocket Visit our website at http://www.overbyte.be
