Some citation from a 2001 publication
https://www.icann.org/news/icann-pr-2001-07-16-en
Not sure if this interim measure progressed any further...
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Advisory: Equitable Allocation of Shared Registration System
(16 July 2001) In recent weeks, some registrars have reported difficulty in accessing the .com/.net/.org Shared Registration System during the hours in which expiring names are deleted. Upon investigation, it appears that a significant portion of the available bandwidth and connections is being consumed during these hours by a few registrars making very large numbers of queries for the names expected to expire.
Under VeriSign's Registry Agreements with ICANN, it is obligated to provide all accredited registrars "with equivalent access to its Registry Services, including to its shared registration system." VeriSign Registry proposed that, as an interim measure, it would place a uniform limit of 250 simultaneous connections and 256k bandwidth applied to each accredited registrar. ICANN has advised VeriSign Registry that these limitations appear consistent with its Registry Agreements. These limits will apply beginning tomorrow, Tuesday, 17 July 2001.
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Letter from Verisign to Registrars
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To All Registrars:
VeriSign Global Registry Services
is responsible for ensuring equivalent access to the Shared Registration System (SRS) by all registrars. Recently, the deletion and subsequent availability of large numbers of domain names have caused a domain "land rush" during certain hours of the day. During these daily "land rushes" some registrars acquire unnecessarily large numbers of RRP sessions, making it difficult for other registrars to acquire the minimal number needed to conduct normal business. Whether this is due to inefficient registrar systems, or a conscious desire to block competition by
monopolizing RRP connections, it is a behavior that cannot be supported or condoned. VeriSign GRS has been working with ICANN to determine an access policy that
will address this abusive behavior while protecting the equivalent access requirements of the COM, NET and ORG Registry Agreements. Our goal is to protect the equivalent access of each registrar without impacting legitimate business operations.
The first step in this process will be to limit the total bandwidth any single registrar can consume, along with the total number of RRP sessions any single registrar can simultaneously open. Beginning Tuesday July 17, each ICANN accredited registrar will be limited to 256K in bandwidth and 250 simultaneous RRP connections.
As always, we recommend each registrar evaluate the efficiency of their systems. VeriSign GRS will share with each registrar their bandwidth utilization and RRP connection trends, in addition to efficiency (i.e., number of transactions per connection).
RRP bandwidth and connections will always be a finite commodity. The recent "land rush" events indicate that the informal measures we have relied on in the past will not ensure that all registrars have fair access to this commodity. VeriSign GRS recognizes that, although they should be helpful in the short term, the bandwidth and connection limitations described above will not ensure access in all load circumstances and are only a partial solution.
We will therefore be working with registrars and ICANN to develop fair and effective longer-term means of providing every registrar appropriate access to the SRS.
