CA Client Automation - 14.0

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Phase 4 Transfer Mechanism Selection

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cla140
Contents
The final phase of the transfer optimization process, Phase 4, includes the selection of an appropriate transfer mechanism.
DTS supports three data transfer mechanisms.
  • Point-to-point
  • Fanout
  • Point-to-many
The default is the point-to-point mechanism. DTS automatically decides which mechanism to use, by the specification of the active transfers and the configuration of the network.
When activating multiple transfers through a transfer group, use of the point-to-point mechanism involves multiple reads, multiple sends (across the network), and multiple writes for each parcel of data processed. However, fanout results in a single read, with multiple sends and multiple writes.
The most efficient mechanism is point-to-many, which means a single read, a single send, and multiple writes. However, it is not possible to use fanout or point-to-many unless the transfer objects involved have certain property values in common.
Transfer Resource Utilization
Note the following considerations when choosing transfer mechanisms:
  • Broadcast is less resource-intensive than fanout.
  • Fanout is less resource-intensive than point-to-point.
For a one-to-many transfer, if the parameters for broadcast are supplied (and if the transfer is not resolved to an existing transfer held in the TOS, by the duplicate transfer resolution process), then broadcast is selected preferentially to fanout, and fanout preferentially to point-to-point. This preferential ordering of protocols is independent of the precedence rules governing parameter value selection.
Relationship Between Broadcasts and Link or Container Properties
If you define broadcast parameters on a container, but not on a link to that container, it does not prevent the use of the broadcast protocol.
Point-to-Point Transfers
Point-to-point transfers are those in which data is sent from a single initiator computer to a single responder computer. This type of transfer is the simplest, because data is only being sent once to a single destination. Point-to-point transfers include the following properties:
  • Point-to-Point Protocol
    Specifies the communications protocol to use during the point-to-point transfer.
  • Point-to-Point Address
    Specifies the address to use for a point-to-point transfer to this machine.
  • Point-to-Point Parameters
    Specifies any point-to-point protocol-specific parameters to take into account when performing a point-to-point data transfer to this machine.
For detailed information, see the
DTSCLI Command Reference Guide
.
Fanout Transfers
Fanout transfers are those in which data is sent to multiple responding machines using a direct point-to-point communications protocol. The fanout transfer mechanism is used across any network. Point-to-point communication links are established with all of the end systems. The source data is then read once and sent many times through each link. This can increase efficiency considerably where read I/O is slow or slow/CPU bound read filtering is specified (for example, compression or encryption).
You can only use the fanout transfer mechanism if the input and initiator machine for all transfer objects in the transfer group are identical.
Fanout transfers include the following properties:
  • Fanout Protocol
    Specifies the communications protocol to use during the fanout transfer.
  • Fanout Address
    Specifies the address to use when a fanout data transfer is sent to this machine.
  • Fanout Parameters
    Specifies special parameters that are to be supplied to the protocol. Fanout is a transfer mechanism that transfers data by reading the data once and then sending it multiple times, once to each of the target responders.
For detailed information, see the
DTSCLI Command Reference Guide
.
Fanout Transfer Criteria
You can combine two or more point-to-point transfers activated at the same time (that is, in the same transfer group) into a fanout transfer if the following are the same:
  • Input data
  • Output data
  • Initiating machine
  • Initiator security tokens (the initiator user and password) for each transfer
  • Responder security tokens (the responder user and password) for each transfer
  • Read parcel and read file filters
  • Parcel size
Point-to-Many Transfers
Point-to-many transfers are those where data is sent to multiple responding machines using a point-to-many protocol, such as BCAST (IP Broadcast) or MCAST (IP Multicast). You can only use the point-to-many transfer mechanism on IP-based networks since the mechanism uses the features of the BCAST and MCAST protocols (which use UDP).
DTS supports IPv4 broadcast and IPv4/IPv6 multicast addressing. The BCAST point-to-many protocol is only for use with IPv4 addresses. If you want to perform a broadcast-type transfer over an IPv6 network, use the MCAST protocol with the relevant IPv6 multicast address.
You can only use the point-to-many transfer mechanism if the input, initiator machine, and output for all transfer objects in the transfer group are identical.
Point-to-many transfers include the following properties:
  • Point-to-Many Protocol
    Specifies the communications protocol to use during the point-to-many transfer.
  • Point-to-Many Network Address
    Identifies the primary network address to use when sending data transfers by way of a point-to-many protocol, like broadcast or multicast, to this machine.
  • Point-to-Many Parameters
    Specifies special parameters to supply to the protocol. Point-to-many is a transfer mechanism that transfers data by reading the data once and sending the data once to all target responders at once.
For detailed information, see the
DTSCLI Command Reference Guide
.
Point-to-Many Transfer Criteria
You can combine two or more point-to-point transfers activated at the same time (that is, in the same transfer group) into a point-to-many transfer if the following are the same:
  • Input data
  • Output data
  • Initiating machine
  • Initiator security tokens (the initiator user and password) for each transfer
  • Responder security tokens (the responder user and password) for each transfer
  • All filters
  • Point-to-many protocol properties (are BCAST or MCAST)
  • Point-to-many network address properties and are not empty