MultiCast and broadcast comm.

Hi all,
here is my issue : I have a server sending messages (via UDP) on the network. I have multiple client reading these. To do this I have ti use java socket and I have 2 solutions :
- use Socket and send/read DatagramSocket : the problem is I can't have multiple client reading the same port number on the same computer : socket aloready bind exeption
- use MulticastSocket : Several clients can now read the same port number from the same computer but if I am disconnected from the network, I have a SocketException (error setting options).
I user j2sdk 1.4.2 under win XP...
Thanks for help !

hello,
i have got the same problem: java.net.SocketException: error setting options while my network is disconnect. What exaclty do you mean with "ex. reconntect"

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What is the diffrence between multicasting and broadcasting?

hi friends
What is the diffrence between multicasting and broadcasting?
i'm bit confused in multicasting and broadcasting.

Broadcasts go everywhere within a range determined by the sender.
Broadcasting is deprecated and unliikely to go beyond the nearest router.
Multicasts go everywhere where receivers have declared they are present.
Multicast can be implemented beyond routers in a WAN which you control but ISP routers generally don't support it.

ACL restriction of multicast and broadcast on SRW2016

Hello all,
I seem to be having difficulty setting up an ACL that restricts multicast and broadcast packets to a specified port on the SRW2016.
In brief, I have one (physical) port that I need to prevent any broadcast or multicast packets from being sent to. I need to allow clients which are on that port to send broadcast, however. My take on this was to create an ACL with one rule of the type:
Type: Deny
Protocol: Any
Source IP: 10.0.0.0/255.255.255.255
Destination IP: 224.0.0.0/0.255.255.255
Another type I tried was a 2-rule ACL to explicitly allow only a valid sender and deny all:
Type: Allow
Protocol: UDP
Dest Port: 1234
Source IP: 10.1.0.100/0.0.0.0
Dest IP: 10.1.0.101/0.0.0.0
Type: Deny
Protocol: All
I have tried various permutations these types of ACL (changing ordering, etc) but everything I have tried so far has allowed the multicast packets through unless I block it at the sending port (which obviously blocks it from all ports).
Any suggestions or comments would be appreciated. Is what I'm trying to do even possible in the SRW2016?
Thanks,
Mike

Just to make sure I was creating/applying the ACLs correctly, I did a simple test with a very basic rule: I just set type to deny (basically a deny all rule). I applied this rule to one port of the switch and verified that it was working by attempting to access the switch's web configuration interface (which correctly was inaccessable). However, the multicast packets were still being delivered (verified via both an Ethernet dump and visual inspection of the switch's LED).
Based on the above information, I feel it's fairly safe to say that Multicast is not filtered correctly via ACLs on the SRW2016. Apparently Multicast packets take a different logical path than "normal" packets. Since I don't expect an immediate firmware patch, I suspect that I need to see if I can get a router in addition or as a replacement for the switch.
Edit: I found a method that appears to restrict the multicast packets via the "Bridge Multicast" interface (basically created a rule for the MAC related to my multicast address, set to Forbidden on one port, but this is not a generic solution for all multicast and I don't seem to be able to have more than 1 MAC address in the list...), but broadcast still gets through, regardless of the ACL I set up for the port.
I'm beginning to wonder if my understanding of ACLs is flawed - does anyone know if they're applied to incoming packets for a port, outgoing packets for a port or both? My assumption was both, but if the rule were only applied to incoming packets, it would explain the behavior I'm observing.
Message Edited by michael.beresford on 03-02-2009 02:46 PM

Data socket and broadcast address

it's posible to use broadcast or multicast address to get resources in a local net?, in order not to specify the exact ip address where the resource is located.
many thanks in advance
Mikel Eguiraun

Hi,
you can broadcast using broadcast IP addresses (see link):
http://www.freesoft.org/CIE/RFC/922/10.htm
A broadcast is a data packet that is destined for multiple hosts. Broadcasts can occur at the data link layer and the network layer. Data-link broadcasts are sent to all hosts attached to a particular physical network. Network layer broadcasts are sent to all hosts attached to a particular logical network. The Transmission Control Protocol/Internet Protocol (TCP/IP) supports the following types of broadcast packets:
•All ones—By setting the broadcast address to all ones (255.255.255.255), all hosts on the network receive the broadcast.
•Network—By setting the broadcast address to a specific network number in the network portion of the IP address and setting all ones in the host portion of the broadcast address, all hosts on the specified network receive the broadcast. For example, when a broadcast packet is sent with the broadcast address of 131.108.255.255, all hosts on network number 131.108 receive the broadcast.
•Subnet—By setting the broadcast address to a specific network number and a specific subnet number, all hosts on the specified subnet receive the broadcast. For example, when a broadcast packet is set with the broadcast address of 131.108.4.255, all hosts on subnet 4 of network 131.108 receive the broadcast.
Also on the next link you can find multicast addresses explanation:
http://www.cisco.com/univercd/cc/td/doc/cisintwk/ito_doc/ipmulti.htm#wp1020564
You can find several examples of UDP Multicast and broadcast on the Examples of labview (go to Help
-> Find examples -> Search and then you write UDP).
Normally broadcasting and multicasting use that protocol (UDP) due to the fact it do not need an ACK in the communication. If you plan to use TCP then you will need a connection for each computer (IP). There are also examples with labview of TCP with multiple connections.
Hope that info helps u,
Regards,
Jaime Cabrera
NI Applications Engineering Spain

Difference between Implicit and Explicit Commit

Hi All ,
Can some one pls let me know the difference between Implicit commit and Explicit Commit .
Thanks in Advance..

>
Kalyan wrote:
> Hi,
>
> An explicit commit happens when we execute an SQL "commit" command.
>
> Implicit commits occur without running a commit command and occur only when certain SQL (DDL) statements are executed
>
> (Ie, INSERT,UPDATE OR DELETE Statements)
> >
> Hope this is clear & Helpful Short and Simple.
>
> Thanks
> Kalyan
Highlighted bit is incorrect.

Autocommit and Cursor commit Behaviour

Hi,
I need help to set and get the Autocommit and Cursor commit behavior attributes
in Oracle.
AUTOCOMMIT:
For DDL Statement, this attribute is set while executing the OCIStmtExecute() api
as below:-
r = OCIStmtExecute(d->svc, d->sql, d->err, 1,0,
(CONST OCISnapshot *) NULL,
(OCISnapshot *) NULL,
d->transaction ? OCI_DEFAULT :                                         OCI_COMMIT_ON_SUCCESS);
For DML Statement, from the OCI documentation the database parameter attributes
support OCI_ATTR_AUTOCOMMIT_DDL with the values OCI_AC_DDL and OCI_NO_AC_DDL.
Since this is a parameter attribute, I couldn't set using OCIAttrSet() API.
I need help in implementing AUTOCOMMIT for both DDL / DML statements.
CURSOR COMMIT BEHAVIOUR:
Similarly, I have observed that Oracle support cursor commit behavior attributes
using OCI_ATTR_CURSOR_COMMIT_BEHAVIOR and the attribute values are OCI_CURSOR_OPEN and OCI_CURSOR_CLOSED.
I have tried setting this attribute as below:-
ub1 nCommitType = OCI_CURSOR_OPEN;
oraRC = OCIAttrSet((dvoid *)d->svc, (ub4)OCI_HTYPE_SVCCTX,
     (dvoid *)&nCommitType,
     (ub4)sizeof(nCommitType),
     OCI_ATTR_CURSOR_COMMIT_BEHAVIOR, d->err);
This always fails with the error ORA-24315: illegal attribute type.
I need help in setting this attribute using OCI.
Another approach to set Autocommit / Close Cursor attributes:-
Oracle support SET commands for autocommit and closecursor, I have prepared
and executed these set commands using OCIStmtPrepare and OCIStmtExecute api. The OCIStmtExecute() API fails to execute the below command texts.
SET AUTOCOMMIT ON/OFF
SET CLOSECURSOR ON/OFF
Is it the right method of setting these attributes?
Thanks,
Sankar.P.

Hi.
You are trying to commit "child" information before your Parent information is commited.
Can you describe how you dragged & droped your views?.
Dragged relationship views or single views?.
Can you put output log with jbo with FINEST level?.
To find a solution try next solutions:
1) Disable "strong" association between your parent-child entities. To achieve it follow next steps:
- Go to your "Assoc" that describes your foreign key.
- In "Realtionship" tab, "Behaviour" disable "Composition Association".
Image: http://1.bp.blogspot.com/-Em8NZvjOUzo/T_NQbJTcLjI/AAAAAAAAAm4/hPsDwtEhJQ4/s1600/4.png
2) Drag and Drop correct views as a Master-Detail (cascading views in your Data Control).
http://2.bp.blogspot.com/-1By5vNNGMFQ/T_NQdYzexKI/AAAAAAAAAnE/DGn7Gr0RSDw/s1600/6.png (in spanish).
In the image, drag & drop PortalwebView2 is the correct way for Master-Details tables. Probably you dragged PortalwebView1 that have dependecy to master table.
Steps that you have followed:
- Drag & Drop dependen View Object as a Master-Detail with two tables.
- Add Create operations from these views to create Rows.
- Add Commit general operation from Data Control.
Try to drag & drop Master-Detail views correctly before disable association.
PD: To try your model faster run Model project instead of your application.
Regards.
Edited by: Daniel Merchán on 30-jul-2012 12:05

How to get the data from mysql database which is being accessed by a PHP application and process the data locally in adobe air application and finally commit the changes back in to mysql database through the PHP application.

How to get the data from mysql database which is being accessed by a PHP application and process the data locally in adobe air application and finally commit the changes back in to mysql database through the PHP application.

If the data is on a remote server (for example, PHP running on a web server, talking to a MySQL server) then you do this in an AIR application the same way you would do it with any Flex application (or ajax application, if you're building your AIR app in HTML/JS).
That's a broad answer, but in fact there are lots of ways to communicate between Flex and PHP. The most common and best in most cases is to use AMFPHP (http://amfphp.org/) or the new ZEND AMF support in the Zend Framework.
This page is a good starting point for learning about Flex and PHP communication:
http://www.adobe.com/devnet/flex/flex_php.html
Also, in Flash Builder 4 they've added a lot of remote-data-connection functionality, including a lot that's designed for PHP. Take a look at the Flash Builder 4 public beta for more on that: http://labs.adobe.com/technologies/flashbuilder4/

Is it possible to set up my iPad as a video camera and broadcast it real time to a TV via apple TV?

Is it possible to sey up my iPad as a video camera and broadcast it real time to a TV via Apple TV?

Use airplay to send what is on the iPad to your tv.
Since ipad2, you can display exactly what is on the ipad screento a tv via an adaper or via airplay through an apple TV.
http://support.apple.com/kb/ht5209
http://support.apple.com/kb/ht4437
General overview but lacks specifics.
http://accelerateyourmarketing.com/home-video-studio/
Video
https://www.youtube.com/watch?v=ce5FVJi0Uxw

I have to send messages through UDP multicast and unicast from same port. In Labview I tried that it throws error. I heard it is possible by means of Datagram (UDP unicast and multicast) Port Sharing. How can it be achieved in Labview?

I have to send UDP multicast and Unicast messages to a remote port from a single source/local port. I tried by opening UDP unicast and multicast in the same port and got the expected error. I tried by opening a unicast connection and sending unicast messages.After that when multicast messages has to send I closed unicast and opened multicast in the same port.This is not throwing any error. But my requirenment is to comminicate with another application in C ++ which recieves this data, throwing an error of lost connectivity and both the applications are not abled to communicate properly.
In the other application with C++ this is implemented using port sharing. So how port sharing can be implemented in labview so that I can send both multicast and unicast messages from the same port?
Thanks in advance

UDP is a sessionless protocol, meaning that anyone listening on the specified port CAN receive the data. CAN because as you noted there is no guarantee in the protocol that it will be received. And if you send the data not to a specific address but a multicast address not only one computer can receive it but in fact every computer on the same subnet listening to that multicast address and depending on the TTL of the packet also computers in neighbouring subnets, although that last one is not a very reliable operation since routers can be configured to drop multicast packages anyhow despite of a different TTL saying otherwise.
Accordingly there is no real way to make sure that a receiving UDP port is not already in use, since you don't build up a connection. UDP is more or less analogous to shouting your messages through a megaphone, and anyone listening on the right frequency (port) can hear it. You do bind the sender socket to a specific port number but that makes little difference.
Rolf Kalbermatter
CIT Engineering Netherlands
a division of Test & Measurement Solutions

Multicast and wirerless

I have a 4404 controller running 6.0.202 code and more more people have Mac running bonjour and wanting to use Airplay. I see how to turn on Multicasting and even provide a Multicast address for IGMP snooping but does anyone have a good feel as to the overall load Multicast adds to the wireless network?
Thanks,
Gary

It depends on the type of deployment you have.
If the network infrastructure supports multicast, you should enable Multicast - Multicast as the controller multicast mode and choose a multicast address in the 239.X.X.X range.
If your network is not capable of supporting multicast, you would want to select Multicast - Unicast mode. This mode puts a load on the controller and on the wireless network as the Multicast is then sent as a unicast to each access point instead.
These support articles should help you.
Bonjour Deployment Guide
http://www.cisco.com/en/US/products/hw/wireless/ps4570/products_tech_note09186a0080bb1d7c.shtml
Multicast Deployment Guide
https://supportforums.cisco.com/docs/DOC-14713

Report execution for different variant and Broadcast

Hi experts,
i had a situation where i need to broadcast the same report for 100 vendors, but the information in the report will be different and specific to the vendor.
can i create different variant for each vendor and execute the report at the time in background and broadcast that to the vendors.
Is it possible for broadcasting the reports at a time
any idea will be appreciated
regards

Hi akshay
Is it like i can execute the report same time for different variants and broadcast that reports based on that variant to different vendor
for eg User A has to view report with Variant X.
User B has to view same report with variant Y
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http://www.dfarber.com/computer-consulting-blog/2011/1/14/processing-hundreds-of-millions-records-got-much-easier.aspx
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Search for multiple values separated by carriage return and not commas

I have developed a report in BI Publisher that allows a user to enter multiple values that are separated by commas.
Is there any way of entering multiple values that are separated by carriage return and not commas?
Any help would be appreciated.
Thanks

Here below, without function :
SQL> with tbl as
2 (select 0 c1, 'j' c2 from dual union all
3   select 1 c1, 'k' c2 from dual union all
4   select 2 c1, 'l' c2 from dual union all
5   select 3 c1, 'm' c2 from dual union all
6   select 4 c1, 'n' c2 from dual )
7 select *
8 from   tbl
9 where   c1 in (select substr(mystring,instr(mystring,',',1,rownum)+1,instr(mystring,',',1,rownum+1)-instr(mystring,',',1,rownum)-1)
10                 from   (select ','||'&str'||',' mystring from dual)
11                 connect by level <= length(mystring)-length(replace(mystring,','))-1);
Enter value for str: 1,2,3
old 10:                from   (select ','||'&str'||',' mystring from dual)
new 10:                from   (select ','||'1,2,3'||',' mystring from dual)
        C1 C
         1 k
         2 l
         3 m
SQL> /
Enter value for str: 0
old 10:                from   (select ','||'&str'||',' mystring from dual)
new 10:                from   (select ','||'0'||',' mystring from dual)
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Pls, its urgent... change IP,netmask and broadcast on solaris 8- make them permanent after reboot

Hi,
I want to change an IP and netmask and broadcast of a machine using solaris 8 but after I reboot the changes are lost. The IP is remembered but the netmask and broadcast are lost. In /etc/netmasks the last line has the new netmask that I established, all the lines before this line are comment.
I do:
ifconfig bge0 down
ifconfig bge0 new_IP netmask new_netmask broadcast new_broadcast
ifconfig bge0 up
It works for the moement, but after I reboot it does not work any more and I have to do it all again. What should I do to make the changes permanent?
Thank you for your help!
Serban

To make the netmask permanent and with the result the broadcast as well you need to make changes to the /etc/netmask file.
You say that u have done it but it seems that the entry is not right.
The way to make the entries is to have the proper network no followed by the netmask.Calculate the Network Number based on the IP and netmask and put in the right entries.
The entry shd be like
192.168.1.0 255.255.255.0
Which means that for all the IP addresses in the range 192.168.1 would have the subnet mask of 255.255.255.0
And i suppose u have the right ip address in the /etc/hosts file.

Can I have 2 routers with different security and broadcast modes off same modem?

Hi
Apologies for not being too technical. The background is that I have a mac and a dell laptop, both of which used to work off a Linksys WRT54G wireless router even though both computers are set up for N routers. I then bought a Logitech Squeezebox internet radio, again working off the Linksys G. The security on all 3 was WEP.
I was then advised to upgrade my router to N and change security to WPA. I bought a Netgear WNR2000 N wireless router as the local shop did not have any linksys n routers. I tried to set up the three devices to this router but it seems that the radio will only broadcast G and WEP security.
It then appeared that I would have to downgrade the other two computers back to G and WEP also and when I did that the internet speed really slowed down.
My query is this, can I set up the Netgear N to be linked to my modem and broadcasting at N and WPA, thus linking my computers at top speed, and then can I link my Linksys to my Netgear and have that broadcast a different network on G/WEP for my radio? If I can or if there is a better solution could someone tell me in easy steps how to do it?
Very much obliged.

You don't have to downgrade your router. Just enable mixed mode so it will allow wireless N and G devices to connect to the router. However, it will share the same wireless security mode.
With regards to your query, the answer is yes. You can setup two (2) wireless routers, one providing N and WPA while the other one providing G and WEP. It might be a little complicated though. You have to cascade the routers. Both should have different SSID and channel.
Try this setup first before changing the wireless options.

MultiCast and broadcast comm.

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