SE1451512A1

SE1451512A1 - Secure communication in an energy management system

Info

Publication number: SE1451512A1
Application number: SE1451512A
Authority: SE
Inventors: Ewa Hansen; Tomas Lennvall; Larisa Rizvanovic; Judith Rossebø; Pia Stoll
Original assignee: Abb Ag
Priority date: 2012-06-26
Filing date: 2012-06-26
Publication date: 2014-12-10
Also published as: WO2014000773A1; DE112012006607T5

Abstract

The present invention relates to a method of an energy management gateway located at the premises of a user and holding an identifier (ID) of said gateway, the method comprising: applying (6) a hash function to the gateway ID to form an alias ID; associating (6o2)the alias ID with data relating to the energy management of the user premises to form an energy information message; and sending (6) the energy information message to a service provider. The present invention also relates to a method of a service provider server receiving the energy information message, as well as to the energy management gateway and the service provider server.(Fig 6)

Description

SECURE COMMUNICATION IN AN ENERGY MANAGEMENTSYSTEM TECHNICAL FIELD The invention relates to an energy management gateway as well as to a server of a service provider, and methods thereof.

BACKGROUND Demand response (DR) services require communications between theindustrial / residential buildings energy management systems (EMS) and theexternal service provider. The external service provider may send DR signalsand also collect energy consumption data from the different households inthe residential building, likewise from tenants/clients in the Industrialbuilding. Other information of importance to the energy management in theresidential building may also be communicated to an external serviceprovider, for example, information about the home automation systemsettings. This information may be cryptographically protected whentransported between the residential building and the external serviceprovider using a communications security protocol such as transport layersecurity (TLS) or internet protocol security (IPsec). In this way, personal orpotentially sensitive business data is protected when transmitted via e.g. the internet.

Privacy of personal data is an issue when energy consumption and otherpersonal data is transported between a household/building and an externalservice provider. The energy consumption or personal data can be securelytransferred over a TCP/ IP network using e.g. TLS at the transport layer orIPsec at the network layer for securing the communications. If for whateverreason the communications security solution is compromised so that anunauthorized party is able to gain access to the information exchangedbetween the household/residential building or industrial building, a privacyconcern is that it should not be possible to connect the energy consumption information or other personal data to the person it is related to.

Additionally, in some cases, it is desirable that a third party service providershould be able to collect energy data in order to analyse energy usagepatterns and research future developments for energy management etc.without compromising the privacy of the individual users and without being able to connect the data to any specific user.

WO 2011/ 143712 discloses a encrypted transmissions between a resourcemanagement client and server via a wireless area network (WAN). The servermay be operated by an energy supply company (ESCO). According to thedocument, secure communication between the ESCO server and multipleclient sites is facilitated, where each client site has a client apparatus orenergy service gateway (ESBox). A unique identifier as well as at least one encryption key is used for the secure communication.

Privacy of personal data is an issue when energy consumption and otherpersonal data is transported between a household/building and an externalservice provider. The energy consumption or personal data can be securelytransferred over a TCP/ IP network using e.g. TLS at the transport layer orIPsec at the network layer for securing the communications. Thus, theinformation is secure, unless the communications security solution iscompromised so that an unauthorized party is able to gain access to theinformation exchanged between the household/residential building or industrial building, e.g. while it is being transmitted via the internet.

SUMMARY It is an objective of the present invention to improve the security of energy management data sent from a building to a service provider.

It has been realised by the inventors of the present invention that if securitysolution of a secure communication between an energy management gatewayof a residential or industrial building to a server of a service provider iscompromised (e.g. an encrypted transmission is hacked, or the encryptionfails), it will be possible to connect the energy management information, sent with the secure communication, to a person or company to which the information relates. By means of the present invention, it will not be possibleto connect the sent information to a person or company, even if anyencryption of the transmission is e.g. hacked. Additionally, by means of thepresent invention, it will be possible to allow a third party service provider tocollect energy data without compromising the privacy of the individual users and without being able to connect the data to any specific user.

According to an aspect of the present invention, there is provided a method ofan energy management gateway located at the premises of a user and holdingan identifier (ID) of said gateway, the method comprising: applying a hashfunction to the gateway ID to form an alias ID; associating the alias ID withdata relating to the energy management of the user premises to form anenergy information message; and sending the energy information message to a service provider.

According to another aspect of the present invention, there is provided anenergy management gateway located at the premises of a user and holding anidentifier (ID) of said gateway, the gateway comprising: a processor; and astorage unit storing instructions that, when executed by the processor, causethe gateway to: apply a hash function to the gateway ID to form an alias ID;associate the alias ID with data relating to the energy management of the userpremises to form an energy information message; and send the energy information message to a service provider.

According to another aspect of the present invention, there is provided acomputer program product comprising computer-executable components forcausing an energy management gateway to perform an embodiment of agateway method of the present invention when the computer-executable components are run on a processor comprised in the gateway.

According to another aspect of the present invention, there is provided acomputer program comprising computer program code which is able to,when run on a processor of an energy management gateway, cause the gateway to: apply a hash function to a gateway ID of the energy management gateway to form an alias ID; associate the alias ID with data relating toenergy management of the user premises to form an energy information message; and send the energy information message to a service provider.

According to another aspect of the present invention, there is provided acomputer program product comprising a computer program according to anembodiment of a gateway computer program of the present invention and a computer readable means on which the computer program is stored.

According to another aspect of the present invention, there is provided amethod of a server of a service provider, the method comprising receiving anenergy information message comprising energy management data from agateway and an alias ID resulting from a hash function having been appliedto a unique identifier of the gateway in the form of a gateway ID, said gatewaybeing located at a premises of a user; and processing the received energy information.

According to another aspect of the present invention, there is provided aserver of a service provider, the server holding an identifier (ID) of an energymanagement gateway located at the premises of a user, the servercomprising: a processor; and a storage unit storing instructions that, whenexecuted by the processor, cause the server to: apply a hash function to thegateway ID to form an alias ID; receive an energy information message fromthe energy management gateway; and determine that an alias ID included inthe energy information message is the same as the alias ID formed by theserver, whereby the gateway is identified as being associated with energy management data included in the energy information message.

According to another aspect of the present invention, there is provided a computer program product comprising computer-executable components forcausing a server to perform an embodiment of a server method of the presentinvention when the computer-executable components are run on a processor comprised in the server.

According to another aspect of the present invention, there is provided acomputer program comprising computer program code which is able to,when run on a processor of a service provider server, cause the server to:apply a hash function to a gateway ID of an energy management gateway toform an alias ID; receive an energy information message from the energymanagement gateway; and determine that an alias ID included in the energyinformation message is the same as the alias ID formed by the server,whereby the gateway is identified as being associated with energy management data included in the energy information message.

According to another aspect of the present invention, there is provided acomputer program product comprising an embodiment of a server computerprogram of the present invention and a computer readable means on which the computer program is stored.

It is an advantage of any of the aspects of the present invention that thegateway ID is secure, encrypted or otherwise not in plain characters, even ifthe message is intercepted or is mistakenly sent to / received by an unintendedrecipient. Thereby, the energy management information cannot be associatedwith any specific client of the service provider. Even if the message isencrypted and the encryption fails, only the alias ID is obtainable. Only theintended recipient, e.g. a server of the service provider, knows the hashfunction and is able to obtain the gateway ID from the alias ID. Thus, theenergy management gateway is able to communicate about personal energyconsumption to an external service provider in a way that prevents theinformation exchanged from the gateway being linkable to the specific user during transmission.

In some embodiments, the energy management gateway and/ or the serviceprovider server also holds an account ID of the user. Then, the account IDmay be combined with the gateway ID to form a combined gateway ID, beforethe step of applying the hash function to said combined gateway ID. In this way, the identity of the user may be further secured.

In some embodiments, the gateway may encrypt the alias ID by means of apublic key of the service provider before the message is sent. Consequently,the server may decrypt the alias ID of the received energy informationmessage by means of a private key of the service provider. In this way, the identity of the user may be further secured.

In some embodiments, the gateway may encrypt the whole energyinformation message, optionally including the alias ID, by means of a publickey of the service provider before said message is sent. Consequently, theserver may decrypt the received energy information message, optionallyincluding the alias ID, by means of a private key of the service provider. Inthis way, the energy management information of the user may be further secured.

Generally, all terms used in the claims are to be interpreted according to theirordinary meaning in the technical field, unless explicitly defined otherwiseherein. All references to "a/ an/ the element, apparatus, component, means,step, etc." are to be interpreted openly as referring to at least one instance ofthe element, apparatus, component, means, step, etc., unless explicitly statedotherwise. The steps of any method disclosed herein do not have to beperformed in the exact order disclosed, unless explicitly stated. The use of“first”, “second” etc. for different features / components of the presentdisclosure are only intended to distinguish the features/ components fromother similar features/ components and not to impart any order or hierarchy to the features/ components.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is now described, by way of example, with reference to the accompanying drawings, in which:Fig 1 is a schematic block diagram of an energy management system.

Fig 2 is a schematic block diagram of an embodiment of an energy management gateway of the present invention.

Fig 3 is a schematic block diagram of an embodiment of a storage unit of the gateway of fig 2.

Fig 4 is a schematic block diagram of an embodiment of a service provider server of the present invention.

Fig 5 is a schematic block diagram of an embodiment of a storage unit of the server of fig 4.

Fig 6 is a schematic ﬂow chart of an embodiment of a method of an energy management gateway, of the present invention.

Fig 7 is a schematic ﬂow chart of an embodiment of a method of a service provider server, of the present invention.

DETAILED DESCRIPTION The invention will now be described more fully hereinafter with reference tothe accompanying drawings, in which certain embodiments of the inventionare shown. This invention may, however, be embodied in many differentforms and should not be construed as limited to the embodiments set forthherein; rather, these embodiments are provided by way of example so thatthis disclosure will be thorough and complete, and will fully convey the scopeof the invention to those skilled in the art. Like numbers refer to like elements throughout the description.

The gateway ID of the present disclosure may be any number, code or the likewhich can facilitate the identification of the gateway from which the energyinformation message is sent. The service provider can then identify whichgateway the energy management information relates to. The gateway ID may conveniently be a unique ID.

The account ID of the present disclosure may be number, code or the likewhich can facilitate the identification of a user (e.g. customer or client) oraccount to which the sent energy management information relates. The gateway may e.g. be responsible for energy management of a plurality of e.g. apartments (each with a separate user) in a residential building, whereby itmay not be enough to identify the gateway by means of the gateway ID inorder to link the sent energy management information to a specific user. Insuch a case, the account ID may specify which of the gateway users the energymanagement information relates to. Additionally or alternatively, the accountID may specify a type of account the gateway user has with the service provider, e.g. what services etc. the user pays for.

The energy management gateway may be any suitable gateway able to sendan energy information message to a service provider. The gateway may e.g. bean Energy Service Interface/ Home Area Network (ESI/ HAN) gateway. Thegateway is located at the premises of a user. The gateway holds EMS logic forcontrolling/ monitoring electrical load(s) at the user premises according to itsconfiguration mode. The premises may e.g. be a residential or industrialbuilding or other facility. The gateway may also involve control of charging ordischarging of local electricity storage such as batteries or the like, and/ or oflocal energy production e.g. solar or wind power equipment at the userpremises. Information exchanged with the external service provider mayinclude user energy consumption information, information about the energyefficiency of the energy management system and/ or about the homeautomation system or changes to be introduced to settings in the energy management or home automation system.

For the communication with the service provider, the gateway in which theEMS is deployed has a gateway ID and optionally an account ID and/ or asecurity module which provides cryptographic support. Both the gateway ID and the account ID, if used, are known by the external service provider.

In some embodiments, the gateway ID and the account ID are combined andthen encrypted with a hash function. By combining the ID of the gatewaywith the account ID and then applying a cryptographic function it is possibleto create an alias ID that cannot be linked to the user/ customer. This alias IDcan then be included when the energy management data and optionally other information is sent to the external service provider.

Via the gateway, the energy management system of the user premises can beconnected to the external service provider which is authorised by the user,e.g. household/ building manager, to interact with the EMS of the premises.The gateway may, e.g. on the external service provider”s request, connect tothe external service provider and send information in the form of energymanagement data such as EMS settings, stored energy consumption valuesetc., to the external service provider. The external service provider may thenprocess the energy management data in any suitable way, e.g. determiningenergy consumption pattern of different electrical devices at the userpremises and/ or managing an electricity consumption database for moregeneral statistical purposes (in which case the service provider does notnecessarily need to know the gateway ID of the gateway; it may be enoughwith the alias ID).

Any keyed or unkeyed hash function may be used in the present invention,i.e. applied to the gateway ID. Preferably, the hash function is sufficientlystrong such that it is pre-image resistant (i.e. for a given known output it iscomputationally infeasible to find an input (message) that corresponds tothat output) and collision resistant (i.e. it is computationally infeasible to findany two distinct inputs that hash to the same output). The actual hashalgorithm to be used is not considered a part of the invention as it is alwaysbest to follow the recommendations of e.g. NIST (National Institute ofStandards and Technology) etc. and apply a standardized algorithm. Also, therequirement on the strength of the hash algorithm to be used will varysubject to new developments in the field. (e.g., NIST has now deprecated useof SHA-1 for digital signature generation, 10 years ago SHA-1 wasrecommended). Reference is made to FIPS publication 180-2 “!Secure HashStandard”; and A. J. Menezes, P. C. van Oorschot, and S. A. Vanstone,“Handbook of Applied Cryptography”, CRC Press, 1997.

It is also contemplated that an energy information message may be sent fromthe server of the service provider to the gateway in a corresponding way asdescribed herein for a message sent from the gateway to the server. The external service provider may then communicate with the gateway on e. g. energy efficiency analysis and remotely issue automation network settingsupdates to the gateway for increased energy efficiency without compromisingthe privacy of the user. An embodiment of a method of the gateway accordingto the present invention may thus also comprise: receiving a second energyinformation message from the server; and determining that an alias IDincluded in the second energy information message is the same as the aliasID formed by the gateway, whereby the energy management data included inthe energy information message is identified as being associated with thegateway. Similarly, an embodiment of a method of the server according to thepresent invention may thus also comprise: associating the alias ID with datarelating to the gateway to form a second energy information message; and sending the second energy information message to the gateway.

In an alternative embodiment of the server of the service provider, the serverdoes not hold or otherwise know the gateway ID. In this embodiment, theserver and thus the service provider cannot identify the user associated withthe energy information message whereby the user is anonymous andprotected. There may thus be third party service providers who would like tocollect energy data but from whom the identity of the user may desirably bekept secret (anonymized) in accordance with e.g. legal privacy directives.Such an external third party service provider may receive, store and analysethe energy management data received while the identity of each user isanonymous to that third party, since only the alias is made known to saidservice provider. This allows e.g. a third party information managementsystem to be able to collect energy data in order to analyse energy usagepatterns, follow-up and evaluate whether e.g., sustainability goals (reductionof costs, reduction of environmental impact) have been reached and researchfuture developments for energy management etc. without compromising theprivacy of the individual users. The identity of the user whose energy data hasbeen collected is anonymized so that the data cannot be connected to the IlSGT.

Figure 1 schematically illustrates an energy management system (EMS) where an energy management gateway 101 of the EMS communicates with a 11 server 102 of a service provider via a network, e.g. the internet and/ or a widearea network (WAN). The communication may be wired or at least partlywireless. If the communication is at least partly wireless, the gateway 101 maybe configured to connect to the network 103 over a radio interface, while theserver 102 connects to the network 103 via a wired interface. Although, in thepresent disclosure, the transmission of messages from the gateway 101 to theserver 102 (as indicated by the arrow in figure 1) is mostly discussed,transmission of messages from the server 102 to the gateway 101 may also OCCUT.

Figure 2 schematically illustrates an embodiment of an energy managementgateway 101. The gateway 101 comprises a processor 201 e.g. a centralprocessing unit (CPU). The processor 201 may comprise one or a plurality ofprocessing units in the form of microprocessor(s). However, other suitabledevices with computing capabilities could be comprised in the processor 201,e.g. an application specific integrated circuit (ASIC), a field programmablegate array (FPGA) or a complex programmable logic device (CPLD). Theprocessor 201 is configured to run one or several computer program(s) orsoftware stored in a storage unit 202 e.g. a memory. The storage unit 202 isregarded as a computer readable means and may e.g. be in the form of aRandom Access Memory (RAM), a Flash memory or other solid statememory, or a hard disk, or a combination thereof. The processor 201 is alsoconfigured to store data in the storage unit 202, as needed. The gateway 101also comprises a transmitter and a receiver, and optionally (if the gateway isconfigured for communication over a radio interface) an antenna, which maybe combined to form a transceiver 204 or be present as distinct units withinthe gateway 101. The transmitter is configured to cooperate with theprocessor to transform data bits to be transmitted e.g. over a radio interfaceto a suitable radio signal in accordance with the radio access technology(RAT) used by the Radio Access Network (RAN) via which the data bits are tobe transmitted. The receiver is configured to cooperate with the processor201 to transform e.g. a received radio signal to transmitted data bits. The antenna, if used, is used by the transceiver 204 for transmitting and 12 receiving, respectively, radio signals. The gateway 101 also comprises anencryption unit 203 comprised in or in cooperation with the processor 201for e.g. applying the hash function and encrypting and/ or decryptingmessages or parts of messages sent/ received e.g. with a public key of theservice provider (if encryption of the alias ID or the whole energy information message is used).

Figure 3 schematically illustrates an embodiment of the storage unit 202 ofthe gateway 101 of figure 2. The storage unit 202 holds the gateway ID 301 aswell as software (SW), i.e. computer program/computer-executablecomponents, 303 which can be accessed and executed by the processor 201for running and controlling the gateway 101. If an account ID 302 is used, said account ID is also held by the storage unit 202.

Figure 4 schematically illustrates an embodiment of a service provider server102. The server 102 comprises a processor 401 e.g. a central processing unit(CPU). The processor 401 may comprise one or a plurality of processing unitsin the form of microprocessor(s). However, other suitable devices withcomputing capabilities could be comprised in the processor 401, e.g. anapplication specific integrated circuit (ASIC), a field programmable gate array(FPGA) or a complex programmable logic device (CPLD). The processor 401is configured to run one or several computer program(s) or software stored ina storage unit 402 e.g. a memory. The storage unit 402 is regarded as acomputer readable means and may e.g. be in the form of a Random AccessMemory (RAM), a Flash memory or other solid state memory, or a hard disk,or a combination thereof. The processor 401 is also configured to store datain the storage unit 402, as needed. The server 102 also comprises atransmitter and a receiver, which may be combined to form a transceiver 404or be present as distinct units within the server 102. The transmitter isconfigured to cooperate with the processor to transform data bits to betransmitted e.g. over a wired interface. The receiver is configured tocooperate with the processor 401 to transform a received signal totransmitted data bits. The server 102 also comprises an encryption unit 403 comprised in or in cooperation with the processor 401 for e.g. applying the 13 hash function and encrypting and/ or decrypting messages or parts ofmessages sent/ received e.g. with a public key of the service provider (if encryption of the alias ID or the whole energy information message is used).

Figure 5 schematically illustrates an embodiment of the storage unit 402 ofthe server 102 of figure 4. The storage unit 402 holds a gateway ID 501 aswell as software (SW), i.e. computer program/computer-executablecomponents, 503 which can be accessed and executed by the processor 401for running and controlling the server 102. The gateway ID 501 is the gatewayID 301 of the gateway 101 with which the server 102 communicates, but thestorage unit 402 may also hold gateway IDs of other gateways with which theserver 102 communicates. If an account ID 302 is used, said account ID is also held by the storage unit 402.

Figure 6 schematically illustrates a method of an energy managementgateway 101. A hash function is applied 601 to the gateway ID 301 of thegateway 101 to form an alias ID. The gateway ID as well as the hash functionmay be stored in the storage unit 202 of the gateway 101, and the hashfunction may be applied by the processor 201. The gateway ID is in someembodiments a combined gateway ID as discussed herein. The thus formedalias ID is then associated 602 with data relating to the energy managementof the user premises to form an energy information message. The energymanagement data (herein sometimes called energy data) is data to betransmitted to the service provider, informing the service provider about e.g.energy consumption of different electrical devices managed by the EMS and/ or user preferences regarding the energy management. The alias ID maybe comprised in the energy information message or otherwise associated withthe same. The gateway 101 then sends 603 the energy information message to the service provider, e.g. to the server 102.

Figure 7 schematically illustrates a method of a service provider server 102. Ahash function is applied 701 to the gateway ID 501 of the gateway 101 fromwhich an energy information message has been /will be received 702, to form an alias ID of said gateway 101. The gateway ID as well as the hash function 14 may be stored in the storage unit 202 of the gateway 101, and the hashfunction may be applied by the processor 201. The gateway ID is in someembodiments a combined gateway ID as discussed herein. The receiving 702of the message may occur before or after the forming 701 of the alias ID, e.g.the alias ID may be formed 701, for each of the gateways with which theserver 201 communicates (if more than one) pre-emptively whereby theserver 102 may directly identify 703 the gateway from which the message wassent, or the alias ID may be formed in response to receiving a message inwhich case alias IDs for each gateway may be formed until the alias IDassociated with the received 702 message is formed 701. That the alias IDincluded in/ associated with the energy information message is the same asthe alias ID formed 701 by the server 102 is then determined 703, wherebythe gateway 101 is identified as being associated with the energy management data included in the energy information message.

A more specific example of a gateway method in combination with a server method is given below: 1. An ESI/ HAN unique gateway ID 301 and an account ID 302 arecombined and an unkeyed Hash or a keyed Hash is applied 601 to generatethe alias ID. It may be advantageous that a Hash function is chosen as the cryptographic function for ease of computation. 2. With an optional additional step, the alias ID may be encrypted usingthe external service provider”s public key (e.g. a X.509 certificate public key).The alias ID or the public key encrypted alias ID is then included 602 in theenergy information message in the appropriate field (where the user ID is to be included) depending on the message format used. 3. The ESI / HAN gateway then sends 603 the data to the external service provider 102 in an energy information message. 4. Upon receiving 702 the message, the external service provider 102receives the data and, if the optional step 2 has been applied, the alias ID is decrypted using the external service provider”s private key. The authorized external service provider 102 has prior knowledge of the ESI / HAN gatewayunique ID 301/ 501 and account ID 302/ 502 and has already formed 701 thealias ID using this information. The external service provider 102 is therefore able to identify 703 which gateway and account/ user the data belongs too.

The invention has mainly been described above with reference to a fewembodiments. However, as is readily appreciated by a person skilled in theart, other embodiments than the ones disclosed above are equally possible within the scope of the invention, as defined by the appended patent claims.

Claims

1. A method of an energy management gateway (101) located at the premises of auser and holding a unique identifier of said gateway in the form of a gateway ID (301 ),the method comprising: - applying (601) a hash function to the gateway ID (301) to form an alias ID; - associating (602) the alias ID with data relating to the energy management of theuser premises to form an energy information message; and sending (603) the energy information message to a service provider (102); wherein the energy management gateway (101) also holds an account ID (302) of theuser, the method also comprising: combining the gateway ID (301) with the account ID (302) to form a combined gatewayID, before the step of applying (601) the hash function to said combined gateway ID.

2. The method of claim 1, also comprising:encrypting the alias ID by means of a public key of the service provider before the message is sent (603).

3. The method of claim 1, also comprising:encrypting the energy information message by means of a public key of the serviceprovider before said message is sent (603).

4. A computer program product comprising computer-executable components (303)for causing an energy management gateway (101) to perform the method of any oneof claims 1-3 when the computer-executable components are run on a processor (201)comprised in the gateway.

5. A method of a server (102) of a service provider, comprising: - receiving (702) an energy information message comprising energy management datafrom a gateway (101) and an alias ID resulting from a hash function having beenapplied to a unique identifier of the gateway (101) in the form of a gateway ID (301),said gateway being located at a premises of a user; and processing the received (702) energy information; wherein the server holds the gateway ID (301, 501), the method further comprising: - applying (701) a hash function to the gateway ID (501) to form an alias ID; anddetermining (703) that the alias ID comprised in the received (702) energy informationmessage is the same as the alias ID formed (701) by the server (102), whereby thegateway (101) is identified as being associated with the energy management datacomprised in the energy information message; wherein the server (102) also holds an account ID (502) of the user, the methodcomprising: - combining the gateway ID (501) with the account ID (502) to form a combinedgateway ID, before the step of applying (701) the hash function to said combinedgateway ID.

6. The method of claim 5, comprising:decrypting the alias ID of the received energy information message by means of aprivate key of the service provider (102).

7. The method of claim 5, comprising:decrypting the received energy information message by means of a private key of theservice provider (102).

8. A computer program product comprising computer-executable components (503)for causing a server (102) to perform the method of any one of claims 5-7 when thecomputer-executable components are run on a processor (401) comprised in the SGFVGI”.