Table of Contents
nat_bflag (string/integer)user_column (string)domain_column (string)contact_column (string)expires_column (string)q_column (string)callid_column (string)cseq_column (string)methods_column (string)flags_column (string)cflags_column (string)user_agent_column (string)received_column (string)socket_column (string)path_column (string)sip_instance_column (string)attr_column (string)use_domain (integer)desc_time_order (integer)timer_interval (integer)db_url (string)db_mode (integer)matching_mode (integer)cseq_delay (integer)accept_replicated_contacts (integer)replicate_contacts_to (integer)skip_replicated_db_ops (int)max_contact_delete (int)hash_size (integer)regen_broken_contactid (integer)ul_register_domain(name)
ul_insert_urecord(domain, aor, rec, is_replicated)
ul_delete_urecord(domain, aor, is_replicated)
ul_get_urecord(domain, aor)
ul_lock_udomain(domain)
ul_unlock_udomain(domain)
ul_release_urecord(record, is_replicated)
ul_insert_ucontact(record, contact,
contact_info, contact, is_replicated)
ul_delete_ucontact
(record, contact, is_replicated)
ul_delete_ucontact_from_id
(domain, contact_id)
ul_get_ucontact(record, contact)
ul_get_domain_ucontacts
(domain, buf, len, flags)
ul_get_all_ucontacts
(buf, len, flags)
ul_update_ucontact(record, contact,
contact_info, is_replicated)
ul_bind_ursloc( api )
ul_register_ulcb(type ,callback, param)
ul_get_num_users()
List of Tables
List of Examples
nat_bflag parameteruser_column parameteruser_column parametercontact_column parameterexpires_column parameterq_column parametercallid_column parametercseq_column parametermethods_column parameterflags_column parametercflags_column parameteruser_agent_column parameterreceived_column parametersocket_column parameterpath_column parametersip_instance_column parameterattr_column parameteruse_domain parameterdesc_time_order parametertimer_interval parameterdb_url parameterdb_mode parametermatching_mode parametercseq_delay parameteraccept_replicated_contacts
parameterreplicate_contacts_to
parameterskip_replicated_db_ops
parametermax_contact_delete
parameterhash_size parameterregen_broken_contactid parameterUser location module. The module keeps a user location table and provides access to the table to other modules. The module exports no functions that could be used directly from scripts.
How the contacts are matched (for same AOR - Address of Record) is an important aspect of the usrloc modules, especialy in the context of NAT traversal - this raise mre problems since contacts from different phones of same users may overlap (if behind NATs with same configuration) or the re-register contact of same phone may be seen as a new one (due different binding via NAT).
The SIP RFC 3261 publishes a matching algorithm based only on the contact string with callid and cseq number extra checking (if callid is the same, it must have a higher cseq number, otherwise invalid). But as argumented above, this is not enough in NAT traversal context, so the OpenSIPS implementation of contact machting offers more algorithms:
contact based only - strict RFC 3261 compliancy - the contact is matched as string and extra checked via callid and cseq (if callid is the same, it must have a higher cseq number, otherwise invalid).
contact and callid based - an extension of the first case - the contact and callid must match as strings; the cseq must be higher than the previous one - so be careful how you deal with REGISTER retransmissions in this case.
For more details on how to control/select the contact matching algorithm,
please see the module parameter matching_mode at
Section 1.3.23, “matching_mode (integer)”.
Starting from OpenSIPS 1.11, the usrloc module offers the possibility of performing real-time mirroring of the entire in-memory user location information of one OpenSIPS instance to one or more other instances. This module-to-module communication is UDP-based, and it is done through the Binary Interface.
Advantages of replicating user-location data using this feature instead of sending duplicated SIP REGISTER requests:
no message parsing required
reduced bandwith usage
no additional script logic needed
In order to control the DB operations performed by the receiving instance(s), the skip_replicated_db_ops parameter can be set. To summarise, the replication logic works together with the DB modes as follows:
0 (No DB) - only in-memory data is replicated (no DB operations are performed at all)
1 (Write through) and 2 (Write back) - default behaviour on all instances, skip_replicated_db_ops can be set on the receiving ones
3 (DB only) - data replication is OFF
Configuring both receival and sending of usrloc replication packets is trivial and can be done by using the accept_replicated_contacts and replicate_contacts_to parameters of the module.
Note that for certain scenarios, where NAT or multihomed interfaces are involved, you might need to preserve the same interface among all the OpenSIPS servers within the replication cluster. Otherwise when an instance receives a replicated contact for whom it does not have a listener, it will use a different listener of his.
The following modules must be loaded before this module:
Optionally an SQL database module.
clusterer, if replicate_contacts_to parameters is turned on (contact replication via clusterer module).
The name of the branch flag to be used as NAT marker (if the contact is or not natted). This is a branch flag and it will be imported and used by all other modules depending of usrloc module.
WARNING: Setting INT flags is deprecated! Use quoted strings instead! Default value is “NULL” (not set).
Name of column containing usernames.
Default value is “username”.
Name of column containing domains.
Default value is “domain”.
Name of column containing contacts.
Default value is “contact”.
Name of column containing expires value.
Default value is “expires”.
Name of column containing q values.
Default value is “q”.
Name of column containing callid values.
Default value is “callid”.
Name of column containing cseq numbers.
Default value is “cseq”.
Name of column containing supported methods.
Default value is “methods”.
Name of column to save the internal flags of the record.
Default value is “flags”.
Name of column to save the branch/contact flags of the record.
Default value is “cflags”.
Name of column containing user-agent values.
Default value is “user_agent”.
Example 1.12. Set user_agent_column parameter
...
modparam("usrloc", "user_agent_column", "user_agent")
...
Name of column containing the source IP, port, and protocol from the REGISTER message.
Default value is “received”.
Example 1.13. Set received_column parameter
...
modparam("usrloc", "received_column", "received")
...
Name of column containing the received socket information (IP:port) for the REGISTER message.
Default value is “socket”.
Name of column containing the Path header.
Default value is “path”.
Name of column containing the SIP instance.
Default value is “NULL”.
Example 1.16. Set sip_instance_column parameter
...
modparam("usrloc", "sip_instance_column", "sip_instance")
...
Name of column containing additional registration-related information.
Default value is “NULL”.
If the domain part of the user should be also saved and used for identifing the user (along with the username part). Useful in multi domain scenarios. Non 0 value means true.
Default value is “0 (false)”.
If the user's contacts should be kept timestamp ordered; otherwise the contact will be ordered based on q value. Non 0 value means true.
Default value is “0 (false)”.
Number of seconds between two timer runs. The module uses timer to delete expired contacts, synchronize with database and other tasks, that need to be run periodically.
Default value is 60.
URL of the database that should be used.
Default value is “mysql://opensips:opensipsrw@localhost/opensips”.
Example 1.21. Set db_url parameter
...
modparam("usrloc", "db_url", "dbdriver://username:password@dbhost/dbname")
...
The usrloc module can utilize database for persistent contact storage. If you use database, your contacts will survive machine restarts or SW crashes. The disadvantage is that accessing database can be very time consuming. Therefore, usrloc module implements four database accessing modes:
0 - This disables database completely. Only memory will be used. Contacts will not survive restart. Use this value if you need a really fast usrloc and contact persistence is not necessary or is provided by other means.
1 - Write-Through scheme. All changes to usrloc are immediately reflected in database too. This is very slow, but very reliable. Use this scheme if speed is not your priority but need to make sure that no registered contacts will be lost during crash or reboot.
2 - Write-Back scheme. This is a combination of previous two schemes. All changes are made to memory and database synchronization is done in the timer. The timer deletes all expired contacts and flushes all modified or new contacts to database. Use this scheme if you encounter high-load peaks and want them to process as fast as possible. The mode will not help at all if the load is high all the time. Also, latency of this mode is much lower than latency of mode 1, but slightly higher than latency of mode 0.
3 - DB-Only scheme. No memory cache is kept, all operations being directly performed with the database. The timer deletes all expired contacts from database - cleans after clients that didn't un-register or re-register. The mode is useful if you configure more servers sharing the same DB without any replication at SIP level. The mode may be slower due the high number of DB operation. For example NAT pinging is a killer since during each ping cycle all nated contact are loaded from the DB; The lack of memory caching also disable the statistics exports.
In case of crash or restart contacts that are in memory only and haven't been flushed yet will get lost. If you want minimize the risk, use shorter timer interval.
Default value is 0.
What contact matching algorithm to be used. Refer to section Section 1.1.1, “Contact matching” for the description of the algorithms.
The parameter may take the following values:
0 - CONTACT ONLY based matching algorithm.
1 - CONTACT and CALLID based matching algorithm.
Default value is 0 (CONTACT_ONLY).
Delay (in seconds) for accepting as retransmissions register requests with same Call-ID and Cseq. The delay is calculated starting from the receiving time of the first register with that Call-ID and Cseq.
Retransmissions within this delay interval will be accepted and replied as the original request, but no update will be done in location. If the delay is exceeded, error is reported.
A value of 0 disable the retransmission detection.
Default value is “20 seconds”.
Set this to a valid cluster id in order to accept and process user-location related information received from other OpenSIPS instances, that belong to the specified cluster id, through the Binary Interface.
Default value is “0” (no cluster id specified) - Binary Interface listeners (if any) will simply ignore any usrloc-related packets
More details on the user location replication mechanism are available in Section 1.1.2, “Contact replication”
Example 1.25. Setting the accept_replicated_contacts
parameter
...
modparam("usrloc", "accept_replicated_contacts", 1)
...
Defines the OpenSIPS instances that belong to a ceratin cluster which will receive all the user-location related information from this machine (addresses-of-record, contacts), organized into specific events (inserts, deletes or updates)
Default value is 0 (no cluster id specified)
More details on the user location replication mechanism are available in Section 1.1.2, “Contact replication”
Example 1.26. Setting the replicate_contacts_to
parameter
...
modparam("usrloc", "replicate_contacts_to", 1)
...
Prevent OpenSIPS from performing any DB-related contact operations when events are received over the Binary Interface. This is commonly used to prevent unneeded duplicate operations.
Default value is "0" (upon receival of usrloc-related Binary Interface events, DB queries may be freely performed)
More details on the user location replication mechanism are available in Section 1.1.2, “Contact replication”
Example 1.27. Setting the skip_replicated_db_ops
parameter
...
modparam("usrloc", "skip_replicated_db_ops", 1)
...
Relevant only in WRITE_THROUGH or WRITE_BACK schemes. The maximum number of contacts to be deleted from the database at once. Will delete all of them, if fewer after passing through all the contacts.
Default value is "10"
Example 1.28. Setting the max_contact_delete
parameter
...
modparam("usrloc", "max_contact_delete", 10)
...
The number of entries of the hash table used by usrloc to store the location records is 2^hash_size. For hash_size=4, the number of entries of the hash table is 16. Since version 2.2, the maximu size of this parameter is 16, meaning that the hash supports maximum 65536 entries.
Default value is “9”.
Since version 2.2, contact_id concept was introduced. Since this parameter validates a contact each time OpenSIPS is started, there are times when the value of this parameter should be regenerated. That is when location table is being migrated from a version older than 2.2 or when hash_size module parameter is changed. Enabling this parameter will regenerate broken contact id's based on current configurations.
Default value is “0(not enabled)”
Example 1.30. Set regen_broken_contactid parameter
...
modparam("usrloc", "regen_broken_contactid", 1)
...
Deletes an entire AOR record (including its contacts).
Parameters:
table name - table where the AOR is removed from (Ex: location).
AOR - user AOR in username[@domain] format (domain must be supplied only if use_domain option is on).
Deletes a contact from an AOR record.
Parameters:
table name - table where the AOR is removed from (Ex: location).
AOR - user AOR in username[@domain] format (domain must be supplied only if use_domain option is on).
contact - exact contact to be removed
Dumps the entire content of the USRLOC in memory cache
Parameters:
brief - (optional, may not be present); if equals to string “brief”, a brief dump will be done (only AOR and contacts, with no other details)
Adds a new contact for an user AOR.
Parameters:
table name - table where the contact will be added (Ex: location).
AOR - user AOR in username[@domain] format (domain must be supplied only if use_domain option is on).
contact - contact string to be added
expires - expires value of the contact
Q - Q value of the contact
unused - unused attribute (kept for backword compatibility)
flags - internal USRLOC flags of the contact
cflags - per branch flags of the contact
methods - mask with supported requests of the contact
Dumps the contacts of an user AOR.
Parameters:
table name - table where the AOR resides (Ex: location).
AOR - user AOR in username[@domain] format (domain must be supplied only if use_domain option is on).
Synchronizes the contacts from memory with the ones from database. Note that this can not be used when no database is specified or with the DB-Only scheme. Important: make sure that all your contacts are in memory (ul_dump MI function) before executing this command. If the AOR is not specified, the whole table will be synchronized.
Parameters:
table name - table where the AOR resides (Ex: location).
AOR (optional) - user AOR in username[@domain] format (domain must be supplied only if use_domain option is on).
Exported statistics are listed in the next sections.
Number of AOR existing in the USRLOC memory cache for that domain - can not be resetted; this statistic will be register for each used domain (Ex: location).
Number of contacts existing in the USRLOC memory cache for that domain - can not be resetted; this statistic will be register for each used domain (Ex: location).
Total number of expired contacts for that domain - can be resetted; this statistic will be register for each used domain (Ex: location).
This event is raised when a new AOR is inserted in the USRLOC memory cache.
Parameters:
aor - The AOR of the inserted record.
This event is raised when a new AOR is deleted from the USRLOC memory cache.
Parameters:
aor - The AOR of the deleted record.
This event is raised when a new contact is inserted in any of the existing AOR's contact list. For each new contact, if its AOR does not exist in the memory, then both the E_UL_AOR_CREATE and E_UL_CONTACT_INSERT events will be raised.
Parameters:
aor - The AOR of the inserted contact.
uri - The contact URI of the inserted contact.
received - IP, port and protocol the registration message was received from. If these have the same value as the contact's address (see the address parameter) then the received parameter will be an empty string.
path - The PATH header value of the registration message.(empty string if not present)
qval - The Q value (priority) of the contact (as integer value from 0 to 10).
socket - The SIP socket/listener (as string) used by OpenSIPS to receive the contact registations.
bflags - The branch flags (bflags) of the contact (in integer value of the bitmask)
expires - The expires value of the contact (as UNIX timestamp integer).
callid - The Call-ID header of the registration message.
cseq - The cseq number as an int value.
This event is raised when a contact is deleted from an existing AOR's contact list. If the contact is the only one in the list then both the E_UL_AOR_DELETE and E_UL_CONTACT_DELETE events will be raised.
Parameters: same as E_UL_CONTACT_INSERT event
The function registers a new domain. Domain is just another name for table used in registrar. The function is called from fixups in registrar. It gets name of the domain as a parameter and returns pointer to a new domain structure. The fixup than 'fixes' the parameter in registrar so that it will pass the pointer instead of the name every time save() or lookup() is called. Some usrloc functions get the pointer as parameter when called. For more details see implementation of save function in registrar.
Meaning of the parameters is as follows:
const char* name - Name of the domain (also called table) to be registered.
The function creates a new record structure and inserts it in the specified domain. The record is structure that contains all the contacts for belonging to the specified username.
Meaning of the parameters is as follows:
udomain_t* domain - Pointer to domain returned by ul_register_udomain.
str* aor - Address of Record (aka username) of the new record (at this time the record will contain no contacts yet).
urecord_t** rec - The newly created record structure.
char is_replicated - Specifies whether this function will be called from the context of a Binary Interface callback. If uncertain, simply use 0.
The function deletes all the contacts bound with the given Address Of Record.
Meaning of the parameters is as follows:
udomain_t* domain - Pointer to domain returned by ul_register_udomain.
str* aor - Address of record (aka username) of the record, that should be deleted.
char is_replicated - Specifies whether this function will be called from the context of a Binary Interface callback. If uncertain, simply use 0.
The function returns pointer to record with given Address of Record.
Meaning of the parameters is as follows:
udomain_t* domain - Pointer to domain returned by ul_register_udomain.
str* aor - Address of Record of request record.
The function lock the specified domain, it means, that no other processes will be able to access during the time. This prevents race conditions. Scope of the lock is the specified domain, that means, that multiple domain can be accessed simultaneously, they don't block each other.
Meaning of the parameters is as follows:
udomain_t* domain - Domain to be locked.
Unlock the specified domain previously locked by ul_lock_udomain.
Meaning of the parameters is as follows:
udomain_t* domain - Domain to be unlocked.
Do some sanity checks - if all contacts have been removed, delete the entire record structure.
Meaning of the parameters is as follows:
urecord_t* record - Record to be released.
char is_replicated - Specifies whether this function will be called from the context of a Binary Interface callback. If uncertain, simply use 0.
The function inserts a new contact in the given record with specified parameters.
Meaning of the parameters is as follows:
urecord_t* record - Record in which the contact should be inserted.
str* contact - Contact URI.
ucontact_info_t* contact_info - Single structure containing the new contact information
char is_replicated - Specifies whether this function will be called from the context of a Binary Interface callback. If uncertain, simply use 0.
The function deletes given contact from record.
Meaning of the parameters is as follows:
urecord_t* record - Record from which the contact should be removed.
ucontact_t* contact - Contact to be deleted.
char is_replicated - Specifies whether this function will be called from the context of a Binary Interface callback. If uncertain, simply use 0.
The function deletes a contact with the given contact_id from the given domain.
Meaning of the parameters is as follows:
udomain_t* domain - Domain where the contact can be found.
uint64_t contact_id - Contact_id identifying the contact to be deleted.
The function tries to find contact with given Contact URI and returns pointer to structure representing the contact.
Meaning of the parameters is as follows:
urecord_t* record - Record to be searched for the contact.
str_t* contact - URI of the request contact.
The function retrieves all contacts of all registered users from the given doamin and returns them in the caller-supplied buffer. If the buffer is too small, the function returns positive value indicating how much additional space would be necessary to accommodate all of them. Please note that the positive return value should be used only as a “hint”, as there is no guarantee that during the time between two subsequent calls number of registered contacts will remain the same.
If flag parameter is set to non-zero value then only contacts that have the specified flags set will be returned. It is, for example, possible to list only contacts that are behind NAT.
Meaning of the parameters is as follows:
udomaint_t* domain - Domain from which to get the contacts
void* buf - Buffer for returning contacts.
int len - Length of the buffer.
unsigned int flags - Flags that must be set.
The function retrieves all contacts of all registered users and returns them in the caller-supplied buffer. If the buffer is too small, the function returns positive value indicating how much additional space would be necessary to accommodate all of them. Please note that the positive return value should be used only as a “hint”, as there is no guarantee that during the time between two subsequent calls number of registered contacts will remain the same.
If flag parameter is set to non-zero value then only contacts that have the specified flags set will be returned. It is, for example, possible to list only contacts that are behind NAT.
Meaning of the parameters is as follows:
void* buf - Buffer for returning contacts.
int len - Length of the buffer.
unsigned int flags - Flags that must be set.
The function updates contact with new values.
Meaning of the parameters is as follows:
urecord_t* record - Record in which the contact should be inserted.
ucontact_t* contact - Contact URI.
ucontact_info_t* contact_info - Single structure containing the new contact information
char is_replicated - Specifies whether this function will be called from the context of a Binary Interface callback. If uncertain, simply use 0.
The function imports all functions that are exported by the USRLOC module. Overs for other modules which want to user the internal USRLOC API an easy way to load and access the functions.
Meaning of the parameters is as follows:
usrloc_api_t* api - USRLOC API
The function register with USRLOC a callback function to be called when some event occures inside USRLOC.
Meaning of the parameters is as follows:
int types - type of event for which the callback should be called (see usrloc/ul_callback.h).
ul_cb f - callback function; see usrloc/ul_callback.h for prototype.
void *param - some parameter to be passed to the callback each time when it is called.
Table 3.1. Top contributors by DevScore(1), authored commits(2) and lines added/removed(3)
| Name | DevScore | Commits | Lines ++ | Lines -- | |
|---|---|---|---|---|---|
| 1. | Jan Janak (@janakj) | 421 | 117 | 15689 | 10095 |
| 2. | Bogdan-Andrei Iancu (@bogdan-iancu) | 223 | 130 | 3899 | 3463 |
| 3. | Liviu Chircu (@liviuchircu) | 68 | 42 | 1819 | 566 |
| 4. | Ionut Ionita (@ionutrazvanionita) | 41 | 24 | 1099 | 413 |
| 5. | Daniel-Constantin Mierla (@miconda) | 40 | 29 | 544 | 308 |
| 6. | Jiri Kuthan (@jiriatipteldotorg) | 36 | 25 | 975 | 120 |
| 7. | Henning Westerholt (@henningw) | 22 | 11 | 462 | 356 |
| 8. | Razvan Crainea (@razvancrainea) | 18 | 13 | 328 | 58 |
| 9. | Andrei Pelinescu-Onciul | 17 | 13 | 151 | 91 |
| 10. | Vlad Paiu (@vladpaiu) | 12 | 10 | 112 | 42 |
All remaining contributors: Nils Ohlmeier, Eseanu Marius Cristian (@eseanucristian), Ovidiu Sas (@ovidiusas), Ionel Cerghit (@ionel-cerghit), Maksym Sobolyev (@sobomax), Andrei Dragus, Dusan Klinec, Andrei Datcu (@andrei-datcu), Juha Heinanen (@juha-h), Anca Vamanu, Vlad Patrascu (@rvlad-patrascu), Marcus Hunger, Jamey Hicks, Andreas Granig, Jeffrey Magder, Phil D'Amore, Norman Brandinger (@NormB), David Sanders, Konstantin Bokarius, Klaus Darilion, Iouri Kharon, Matthew M. Boedicker, UnixDev, Edson Gellert Schubert, Elena-Ramona Modroiu, Stephane Alnet.
(1) DevScore = author_commits + author_lines_added / (project_lines_added / project_commits) + author_lines_deleted / (project_lines_deleted / project_commits)
(2) including any documentation-related commits, excluding merge commits. Regarding imported patches/code, we do our best to count the work on behalf of the proper owner, as per the "fix_authors" and "mod_renames" arrays in opensips/doc/build-contrib.sh. If you identify any patches/commits which do not get properly attributed to you, please submit a pull request which extends "fix_authors" and/or "mod_renames".
(3) ignoring whitespace edits, renamed files and auto-generated files
Table 3.2. Most recently active contributors(1) to this module
| Name | Commit Activity | |
|---|---|---|
| 1. | Bogdan-Andrei Iancu (@bogdan-iancu) | Mar 2002 - Jun 2018 |
| 2. | Liviu Chircu (@liviuchircu) | Jan 2013 - Jun 2018 |
| 3. | Razvan Crainea (@razvancrainea) | Jul 2011 - May 2017 |
| 4. | Ionut Ionita (@ionutrazvanionita) | Jul 2015 - Apr 2017 |
| 5. | Ionel Cerghit (@ionel-cerghit) | Jul 2015 - Dec 2016 |
| 6. | Vlad Patrascu (@rvlad-patrascu) | Jul 2016 - Aug 2016 |
| 7. | Ovidiu Sas (@ovidiusas) | Apr 2008 - Mar 2016 |
| 8. | Dusan Klinec | Dec 2015 - Dec 2015 |
| 9. | Eseanu Marius Cristian (@eseanucristian) | Aug 2015 - Sep 2015 |
| 10. | David Sanders | Oct 2014 - Oct 2014 |
All remaining contributors: Andrei Datcu (@andrei-datcu), Stephane Alnet, Vlad Paiu (@vladpaiu), Andrei Dragus, Phil D'Amore, UnixDev, Daniel-Constantin Mierla (@miconda), Henning Westerholt (@henningw), Iouri Kharon, Konstantin Bokarius, Edson Gellert Schubert, Anca Vamanu, Matthew M. Boedicker, Marcus Hunger, Elena-Ramona Modroiu, Jeffrey Magder, Norman Brandinger (@NormB), Andreas Granig, Juha Heinanen (@juha-h), Klaus Darilion, Jan Janak (@janakj), Andrei Pelinescu-Onciul, Jiri Kuthan (@jiriatipteldotorg), Maksym Sobolyev (@sobomax), Jamey Hicks, Nils Ohlmeier.
(1) including any documentation-related commits, excluding merge commits
Last edited by: Bogdan-Andrei Iancu (@bogdan-iancu), Liviu Chircu (@liviuchircu), Razvan Crainea (@razvancrainea), Ionut Ionita (@ionutrazvanionita), Eseanu Marius Cristian (@eseanucristian), Ovidiu Sas (@ovidiusas), Andrei Datcu (@andrei-datcu), Daniel-Constantin Mierla (@miconda), Konstantin Bokarius, Edson Gellert Schubert, Henning Westerholt (@henningw), Marcus Hunger, Elena-Ramona Modroiu, Juha Heinanen (@juha-h), Jan Janak (@janakj), Maksym Sobolyev (@sobomax), Nils Ohlmeier.
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