Multicast Updates

On the Multicast updates tab, you can configure updates transmission on workstations via the multicast protocol.

Set the Enable multicast updates flag to enable transmission of updates to stations via the multicast protocol, in so doing:

•If multicast updates are disabled, updating of all stations is performed only in general mode—via the TCP protocol.

•If multicast updates are enabled, when for all stations connected to this Server updating is performed in two stages:

1.Update via multicast protocol.

2.General update via the TCP protocol.

To setup multicast updates, use the following parameters:

•UDP datagram size (bytes)—size of UDP datagrams in bytes.

Allowed range is 512—8192. To avoid fragmentation, it is recommended to set a value less than MTU (Maximum Transmission Unit) of the network.

•File transmission time (ms.)—during specified time, single update file is transmitted, after that Server starts sending the next file.

All files which failed to transmit at the step of multicast protocol update, will be transmitted at standard update process over the TCP protocol.

•Multicast updates duration (ms.)—duration of update process via multicast protocol.

All files that failed to transmit during update stage via multicast protocol will be transmitted in process of standard update via TCP protocol.

•Packages transmission interval (ms.)—interval of packages transmission to a multicast group.

The low interval value may cause significant losses during package transfer and network overload. It is not recommended to change this parameter.

•Interval between retransmission requests (ms.)—with this interval Agents send requests for retransmission of lost packages.

Server accumulates these requests after that sends lost blocks.

•“Silence” interval on the line (ms.)—when a file transmission is over before allowed time has expired, if during specified “silence” interval no requests from Agents for retransmission of lost packages are received, Server considers that all Agent received updates files and starts sending the next file.

•Retransmission requests accumulation interval (ms.)—during specified interval, Server accumulates requests from Agents for retransmission of lost packages.

Agent request lost packages. Server accumulates these requests during specified time slot after that sends lost blocks.

To specify the list of multicast groups from which multicast updates is available, setup the following parameters in the Multicast groups section:

•Multicast group—IP address of multicast group in which stations receive multicast updates.

•Port—port number of Dr.Web Server network interface, to which transport multicast protocol is bound for updates transmission.

•Interface—IP address of Dr.Web Server network interface, to which transport multicast protocol is bound for updates transmission.

Every line contains setup of one multicast group. To add one more multicast group, click .

When you configure several multicast groups, please note the following features:

•For different Dr.Web Servers, which will distribute multicast updates, must be different multicast groups specified.

•For different Dr.Web Servers, which will distribute multicast updates, must be different Interface and Port parameters specified.

•For using several multicast groups, sets of stations which are included into these groups must not overlap. Thus, each station of anti-virus network can be included only into one multicast group.