When using quotes or extracts, there is no magic figure or percentage that can be applied as each case must be viewed on its own merit. In cases that have come to trial what is clear is that it is the perceived importance of the copied content rather than simply the quantity that counts. If the use has a financial impact on the copyright owner, i. This is not necessarily the case.
Copyright law is principally civil not criminal law, and civil law requires a lower burden of proof. In a criminal case, the defendant is innocent until proven guilty beyond any reasonable doubt. However, in a civil case, the plaintiff must simply convince the court or tribunal that their claim is valid, and that on balance of probability it is likely that the defendant is guilty. A sound recording will have a separate copyright to the underlying work that is featured in the recording.
This means that a new recording of an out of copyright work will still be protected under copyright, even if copyright has expired in the original work. Artist JL Cook's bronze sculptures of rattlesnakes—originally commissioned by the Chiricahua Desert Museum in Rodeo, New Mexico—have been copied and offered for sale on Facebook for a fraction of the price the originals sell at.
You might have seen the adverts on your Facebook feed: an eye-catching sculpture made by an independent artist, offered in a run of repetitive sponsored ads, for a cut-rate price. But if you actually clicked on the link and bought the piece, you would likely either receive nothing or a cheap knockoff with only a passing resemblance to the work pictured in the post. And the artists say Facebook is not doing enough to stop the scammers.
The scam ads started popping up on Facebook less than 24 hours after she had created her own e-commerce website in June to sell works directly to collectors. I have reported over ads on my rattlesnakes alone to Facebook. There are over 93 different URLs that are fake web companies that have my work on them. Cook has reported the fake ads to Facebook, but the company has been slow to respond. Note that the rules specified in section 3. There may be systems that use different subnet masks for different subnets within a single network.
Network- wide distribution of routing information which contains different subnet masks is permitted if all routers in the network are running the extensions presented in this document. However, if all routers in the network are not running these extensions distribution of routing information containing different subnet masks must be limited to avoid interoperability problems.
See sections 3. Each router that implements RIP is assumed to have a routing table. This table has one entry for every destination that is reachable throughout the system operating RIP. Each entry contains at least the following information: - The IPv4 address of the destination. This metric is the sum of the costs associated with the networks that would be traversed to get to the destination.
If the destination is on one of the directly-connected networks, this item is not needed. This will be referred to as the "route change flag. The entries for the directly-connected networks are set up by the router using information gathered by means not specified in this protocol. The metric for a directly-connected network is set to the cost of that network. As mentioned, 1 is the usual cost. In that case, the RIP metric reduces to a simple hop-count.
More complex metrics may be used when it is desirable to show preference for some networks over others e. To support the extensions detailed in this document, each entry must additionally contain a subnet mask. The subnet mask allows the router along with the IPv4 address of the destination to identify the different subnets within a single network as well as the subnets masks of distant networks. These would most likely be routes to hosts or networks outside the scope of the routing system.
They are referred to as "static routes. In order for the protocol to provide complete information on routing, every router in the AS must participate in the protocol. In cases where multiple IGPs are in use, there must be at least one router which can leak routing information between the protocols. All routing update messages are sent from the RIP port. Unsolicited routing update messages have both the source and destination port equal to the RIP port.
Update messages sent in response to a request are sent to the port from which the request came. Specific queries may be sent from ports other than the RIP port, but they must be directed to the RIP port on the target machine. Unless otherwise specified, fields contain binary integers, in network byte order, with the most- significant octet first big-endian. Each tick mark represents one bit.
Every message contains a RIP header which consists of a command and a version number. This section of the document describes version 1 of the protocol; section 4 describes the version 2 extensions. The command field is used to specify the purpose of this message.
The commands implemented in version 1 and 2 are: 1 - request A request for the responding system to send all or part of its routing table. This message may be sent in response to a request, or it may be an unsolicited routing update generated by the sender. For each of these message types, in version 1, the remainder of the datagram contains a list of Route Entries RTEs.
The AFI is the type of address. The metric field contains a value between 1 and 15 inclusive which specifies the current metric for the destination; or the value 16 infinity , which indicates that the destination is not reachable. The RIP protocol allows either of these possibilities. The destinations appearing in request and response messages can be networks, hosts, or a special code used to indicate a default address.
In general, the kinds of routes actually used will depend upon the routing strategy used for the particular network. Many networks are set up so that routing information for individual hosts is not needed. If every node on a given network or subnet is accessible through the same routers, then there is no reason to mention individual hosts in the routing tables. However, networks that include point-to-point lines sometimes require routers to keep track of routes to certain nodes.
Whether this feature is required depends upon the addressing and routing approach used in the system. Thus, some implementations may choose not to support host routes. If host routes are not supported, they are to be dropped when they are received in response messages see section 3. The RIP-1 packet format does not distinguish among various types of address. Fields that are labeled "address" can contain any of the following: host address subnet number network number zero default route Entities which use RIP-1 are assumed to use the most specific information available when routing a datagram.
That is, when routing a datagram, its destination address must first be checked against the list of node addresses.
Then it must be checked to see whether it matches any known subnet or network number. Finally, if none of these match, the default route is used. When a node evaluates information that it receives via RIP-1, its interpretation of an address depends upon whether it knows the subnet mask that applies to the net.
If so, then it is possible to determine the meaning of the address. For example, consider net It has a subnet mask of Thus However, if the node does not know the subnet mask, evaluation of an address may be ambiguous. If there is a non-zero node part, there is no clear way to determine whether the address represents a subnet number or a node address. As a subnet number would be useless without the subnet mask, addresses are assumed to represent nodes in this situation.
In order to avoid this sort of ambiguity, when using version 1, nodes must not send subnet routes to nodes that cannot be expected to know the appropriate subnet mask. Normally hosts only know the subnet masks for directly-connected networks.
This "subnet filtering" is carried out by the routers at the "border" of the subnetted network. These are routers which connect that network with some other network.
Within the subnetted network, each subnet is treated as an individual network. Routing entries for each subnet are circulated by RIP. However, border routers send only a single entry for the network as a whole to nodes in other networks. This means that a border router will send different information to different neighbors.
For neighbors connected to the subnetted network, it generates a list of all subnets to which it is directly connected, using the subnet number. For neighbors connected to other networks, it makes a single entry for the network as a whole, showing the metric associated with that network. This metric would normally be the smallest metric for the subnets to which the router is attached. Similarly, border routers must not mention host routes for nodes within one of the directly-connected networks in messages to other networks.
Those routes will be subsumed by the single entry for the network as a whole. The router requirements RFC [ 11 ] specifies that all implementation of RIP should support host routes but if they do not then they must ignore any received host routes. The special address 0. A default route is used when it is not convenient to list every possible network in the RIP updates, and when one or more closely- connected routers in the system are prepared to handle traffic to the networks that are not listed explicitly.
These routers should create RIP entries for the address 0. The decision as to how routers create entries for 0. Most commonly, the system administrator will be provided with a way to specify which routers should create entries for 0.
For example, an implementor might decide that any router which speaks BGP should be declared to be a default router. It may be useful to allow the network administrator to choose the metric to be used in these entries.
If there is more than one default router, this will make it possible to express a preference for one over the other. The entries for 0. System administrators should take care to make sure that routes to 0.
Thus, routes involving 0. The mechanisms for enforcing this are not specified in this document. Every 30 seconds, the RIP process is awakened to send an unsolicited Response message containing the complete routing table see section 3. When there are many routers on a single network, there is a tendency for them to synchronize with each other such that they all issue updates at the same time.
This can happen whenever the 30 second timer is affected by the processing load on the system. It is undesirable for the update messages to become synchronized, since it can lead to unnecessary collisions on broadcast networks. Therefore, implementations are required to take one of two precautions: - The second updates are triggered by a clock whose rate is not affected by system load or the time required to service the previous update timer.
Implementors may wish to consider even larger variation in the light of recent research results [ 10 ] There are two timers associated with each route, a "timeout" and a "garbage-collection" time. Upon expiration of the timeout, the route is no longer valid; however, it is retained in the routing table for a short time so that neighbors can be notified that the route has been dropped.
Upon expiration of the garbage-collection timer, the route is finally removed from the routing table. The timeout is initialized when a route is established, and any time an update message is received for the route. If seconds elapse from the last time the timeout was initialized, the route is considered to have expired, and the deletion process described below begins for that route.
Deletions can occur for one of two reasons: the timeout expires, or the metric is set to 16 because of an update received from the current router see section 3. This causes the route to be removed from service. Until the garbage-collection timer expires, the route is included in all updates sent by this router. When the garbage-collection timer expires, the route is deleted from the routing table. Should a new route to this network be established while the garbage- collection timer is running, the new route will replace the one that is about to be deleted.
In this case the garbage-collection timer must be cleared. Triggered updates also use a small timer; however, this is best described in section 3. Processing will depend upon the value in the command field.
See sections 4. Normally, Requests are sent as broadcasts multicasts for RIP-2 , from the RIP port, by routers which have just come up and are seeking to fill in their routing tables as quickly as possible. However, there may be situations e. If such a Request is received, the router responds directly to the requestor's address and port. The Request is processed entry by entry. If there are no entries, no response is given.
There is one special case. If there is exactly one entry in the request, and it has an address family identifier of zero and a metric of infinity i. Except for this special case, processing is quite simple. Examine the list of RTEs in the Request one by one. For each entry, look up the destination in the router's routing database and, if there is a route, put that route's metric in the metric field of the RTE.
If there is no explicit route to the specified destination, put infinity in the metric field. Once all the entries have been filled in, change the command from Request to Response and send the datagram back to the requestor. Note that there is a difference in metric handling for specific and whole-table requests. If the request is for a complete routing table, normal output processing is done, including Split Horizon see section 3. If the request is for specific entries, they are looked up in the routing table and the information is returned as is; no Split Horizon processing is done.
The reason for this distinction is the expectation that these requests are likely to be used for different purposes. When a router first comes up, it multicasts a Request on every connected network asking for a complete routing table.
It is assumed that these complete routing tables are to be used to update the requestor's routing table. For this reason, Split Horizon must be done. It is further assumed that a Request for specific networks is made only by diagnostic software, and is not used for routing.
In this case, the requester would want to know the exact contents of the routing table and would not want any information hidden or modified. Because processing of a Response may update the router's routing table, the Response must be checked carefully for validity.
The Response must be ignored if it is not from the RIP port. The datagram's IPv4 source address should be checked to see whether the datagram is from a valid neighbor; the source of the datagram must be on a directly-connected network. It is also worth checking to see whether the response is from one of the router's own addresses.
If a router processes its own output as new input, confusion is likely so such datagrams must be ignored. Again, start by doing validation. Incorrect metrics and other format errors usually indicate misbehaving neighbors and should probably be brought to the administrator's attention.
For example, if the metric is greater than infinity, ignore the entry but log the event. The basic validation tests are: - is the destination address valid e. Again, logging the error is probably a good idea. Once the entry has been validated, update the metric by adding the cost of the network on which the message arrived.
If the result is greater than infinity, use infinity. If there is no such route, add this route to the routing table, unless the metric is infinity there is no point in adding a route which is unusable. Adding a route to the routing table consists of: - Setting the destination address to the destination address in the RTE - Setting the metric to the newly calculated metric as described above - Set the next hop address to be the address of the router from which the datagram came - Initialize the timeout for the route.
If the garbage-collection timer is running for this route, stop it see section 3. If this datagram is from the same router as the existing route, reinitialize the timeout. Next, compare the metrics. If the datagram is from the same router as the existing route, and the new metric is different Malkin Standards Track [Page 27] RFC RIP Version 2 November than the old one; or, if the new metric is lower than the old one; do the following actions: - Adopt the route from the datagram i.
Note that the deletion process is started only when the metric is first set to infinity. If the metric was already infinity, then a new deletion process is not started. If the new metric is the same as the old one, it is simplest to do nothing further beyond re-initializing the timeout, as specified above ; but, there is a heuristic which could be applied.
Normally, it is senseless to replace a route if the new route has the same metric as the existing route; this would cause the route to bounce back and forth, which would generate an intolerable number of triggered updates. Share rip Post more words for rip to Facebook Share more words for rip on Twitter. Time Traveler for rip The first known use of rip was in the 15th century See more words from the same century.
Phrases Related to rip rip off. Style: MLA. Get Word of the Day daily email! Test Your Vocabulary. Can you spell these 10 commonly misspelled words? Love words? Need even more definitions? Homophones, Homographs, and Homonyms The same, but different.
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