#sysmoISIM-SJA5
#sysmoISIMSJA5

sysmoUSIM-SJS1 vs SJA2 vs SJA5 Explained | HKCARD’s MVNO SIM Card ManufacturingMeta Description: Compare sysmoUSIM-SJS1 (2G/3G), sysmoISIM-SJA2 (2G-5G), and sysmoISIM-SJA5 (Rel17 5G SA) programmable SIM cards from sysmocom. Discover how HKCARD Electronics Co., Limited, a leading MVNO SIM card manufacturer, offers comparable MVNO Java SIM cards, LTE 4G USIM cards, and blank SIM cards for global telecom operators.URL: /sysmousim-sjs1-sja2-sja5-comparison-hkcard-programmable-sim-solutions

Evolution of sysmocom Programmable SIM Cards: SJS1 → SJA2 → SJA5sysmocom has developed a lineage of programmable, standards-compliant SIM/USIM/ISIM cards for research, private networks, and open-source cellular ecosystems (e.g., Osmocom, sysmoNITB). Each generation builds on the previous, expanding network support, storage, authentication algorithms, and 5G readiness.

Model
Launch
Status
Primary Focus
Network Support
sysmoUSIM-SJS1
2016
EOL (2020)
2G/3G Java SIM/USIM
GSM, UMTS
sysmoISIM-SJA2
2016
EOL (2023)
2G-5G SIM/USIM/ISIM
GSM, UMTS, LTE, 5G (basic)
sysmoISIM-SJA5
Oct 2023
Current
Full 5G SA (Rel17), HPSIM, GSM-R
2G–5G SA

1. sysmoUSIM-SJS1: The Original 2G/3G Programmable SIMPurpose: Entry-level programmable SIM/USIM for GSM and UMTS networks.Key Features

  • Form Factor: 2FF+3FF (mini+micro) or 2FF+4FF (mini+nano)
  • Storage: 64 kB flash
  • Java Card: Full support (Card Manager, OTA, STK/SAT)
  • Authentication:
    • GSM: COMP128v1 (default), v2/v3, XOR, MILENAGE
    • UMTS: MILENAGE (default), XOR
  • Programmable: IMSI, ICCID, Ki/K/OP/OPC, MSISDN, full filesystem
  • Security: Card-individual ADM key, 3DES OTA keys
  • Tools: pySim-prog.py, sysmo-usim-tool.sjs1
  • Use Case: Private GSM/UMTS networks, Osmocom testing, OAI integration
EOL October 2020 – Replaced by SJA2 due to chip/OS obsolescence.

2. sysmoISIM-SJA2: First Multi-Standard SIM/USIM/ISIMPurpose: First card to integrate SIM + USIM + ISIM for 2G to 5G-ready networks.Key Upgrades from SJS1

Feature
SJS1
SJA2 (Upgrade)
ISIM Support
No
Yes (VoLTE, IMS)
5G Readiness
No
Yes (SUCI via ME)
Form Factor
2FF+3FF/4FF
1FF + perforations + MFF2 (IoT)
Storage
64 kB
64 kB (same)
Standards
GSM/UMTS
ETSI/3GPP up to Rel16
  • Authentication: MILENAGE (default), COMP128v1/v2/v3
  • Java: OTA, STK, applet loading
  • Programming: pySim, sysmo-usim-tool.sja2
  • Pre-provisioned: Test IMSI (999-70), ADM key per card
  • Use Case: VoLTE testing, private LTE, 5G research (limited)
EOL 2023 – Replaced by SJA5 due to chip EOL and 5G demand.

3. sysmoISIM-SJA5: Current 5G SA Flagship (3GPP Release 17)Purpose: Full 5G Standalone (SA) support with all optional files, HPSIM, and GSM-R.Major Enhancements Over SJA2

Feature
SJA2
SJA5 (New)
Flash Storage
64 kB
200 kB (3x more for 5G files, applets)
3GPP Compliance
Up to Rel16
Full Release 17
5G SA Files
Limited
All optional files in DF.5GS
Authentication
MILENAGE, COMP128
+ XOR-2G/3G, TUAK
HPSIM
No
Yes (half-paired 5G auth)
GSM-R Support
No
Yes (railway comms)
SUCI Calculation
ME-dependent
On-card (SJA5-S17 variant)
CPU Variants
Single
9FV (budget) / S17 (premium)
Developer Mode
Writable fields
Enhanced (reduced applet security)
  • Form Factor: 1FF (perforated), MFF2
  • Tools: sysmo-isim-tool.sja5, pySim-prog.py
  • Use Case: 5G SA labs, private 5G, GSM-R, IoT, advanced VoLTE
Current as of 2025 – No successor announced.

Side-by-Side Comparison Table

Feature
SJS1
SJA2
SJA5
Status
EOL (2020)
EOL (2023)
Active
Network Support
2G/3G
2G–5G (basic)
2G–5G SA (Rel17)
SIM/USIM/ISIM
SIM + USIM
SIM + USIM + ISIM
+ HPSIM
Flash Storage
64 kB
64 kB
200 kB
Java Card
Yes
Yes
Yes (enhanced)
Authentication
COMP128, MILENAGE, XOR
MILENAGE, COMP128
+ XOR-2G/3G, TUAK
5G SUCI
No
ME-based
On-card (S17)
Form Factor
2FF+3FF/4FF
1FF + MFF2
1FF + MFF2
Use Case
GSM/UMTS testing
VoLTE, early 5G
5G SA, GSM-R, IoT

HKCARD Electronics Co., Limited: Commercial-Grade AlternativesWhile sysmocom cards excel in research and open-source, HKCARD delivers production-scale, globally deployable programmable SIMs for MVNOs and MNOs.HKCARD Equivalents to sysmocom Lineup

sysmocom Card
HKCARD Solution
Key Advantages
SJS1
2G/3G Java SIM Cards
Bulk supply, OTA, STK
SJA2
MVNO Java SIM + LTE 4G USIM
ISIM/VoLTE, 128K+ flash
SJA5
5G-Ready Programmable USIM (Rel17+)
On-card SUCI, HPSIM, 200 kB+

HKCARD Features Beyond sysmocom

  • Global Scale: Bulk SIM card supply (10K–1M+ units), DDP shipping to 80+ countries
  • Formats: Full/half/quarter SIM, 2FF, MFF2, embedded
  • Compatibility: GSM, WCDMA, LTE, CDMA (RUIM), 5G SA
  • Personalization: IMSI/Ki/OPC encoding, Java applet loading
  • Testing: Full SIM card testing, USIM test solutions (ETSI/3GPP)
  • Markets: Prepaid/postpaid, IoT, MVNOs in Africa, Asia, LATAM
“HKCARD’s programmable SIMs give us SJA5-level 5G control with 100x the scale.” – MVNO Operator

Which Card Should You Use?

Use Case
Recommended
Legacy 2G/3G testing
HKCARD 2G/3G SIM
VoLTE / Early 5G research
HKCARD MVNO Java SIM
Full 5G SA / Rel17 / HPSIM
HKCARD 5G USIM
Open-source lab (Osmocom)
sysmoISIM-SJA5
Commercial MVNO Launch
HKCARD Bulk Supply

Contact HKCARD: Your Global SIM PartnerReady to deploy programmable SIMs at scale? HKCARD offers:

  • MVNO Java SIM Cards (128K–1MB)
  • LTE 4G / 5G USIM (Rel17+)
  • Blank & Replacement SIMs
  • Bulk Orders + DDP Shipping

Email: byronhan@cardmfg.com
Phone: +8615817372512
Website: https://www.cardmfg.com/

  1. sysmoUSIM-SJS1 vs SJA2 vs SJA5: Full Comparison + HKCARD Alternatives
  2. From SJS1 to SJA5: Evolution of Programmable SIMs – HKCARD’s 5G Solutions
  3. sysmoISIM-SJA5 vs HKCARD: 5G SA SIM Cards for MVNOs and Labs
  4. EOL Alert: SJS1 & SJA2 – Upgrade to HKCARD’s Programmable USIM
  5. HKCARD vs sysmocom: Research SIMs vs Global MVNO Deployment

#sysmoUSIMSJS1 #sysmoISIMSJA2 #sysmoISIMSJA5 #ProgrammableSIM #MVNOSIMCard #5GUSIM #JavaSIMCard #SIMCardManufacturer #LTE4GUSIM #HKCARDElectronics

 

Best Regards
Byron

HKCARD ELECTRONICS CO.,LIMITED
Whatsapp/wechat:+8615817372512
Skype/Teams：byron1681
Email：byronhan@cardmfg.com