diff --git a/src/Operations/operations.module.ts b/src/Operations/operations.module.ts
index 8ef5142..c10a345 100644
--- a/src/Operations/operations.module.ts
+++ b/src/Operations/operations.module.ts
@@ -7,9 +7,10 @@ import { OperationsService } from './operations.services';
 
 @Module({
   imports: [
-    TypeOrmModule.forFeature([Alumno, DetalleServicio]), // entidades que usarán las transacciones
+    TypeOrmModule.forFeature([Alumno, DetalleServicio]),
   ],
   controllers: [OperationsController],
   providers: [OperationsService],
 })
 export class OperationsModule {}
+//IO
\ No newline at end of file
diff --git a/src/alumno/entities/student.entity.ts b/src/alumno/entities/student.entity.ts
index e51ce41..6f3c7a1 100644
--- a/src/alumno/entities/student.entity.ts
+++ b/src/alumno/entities/student.entity.ts
@@ -93,6 +93,6 @@ export class Alumno {
   @JoinColumn({ name: 'id_carrera' })
   carrera: Carrera;
 
-  @OneToMany(() => AlumnoSancion, (alusancion) => alusancion.id_cuenta)
+  @OneToMany(() => AlumnoSancion, (alusancion) => alusancion.sancion)
   sanciones: AlumnoSancion[];
 }
diff --git a/src/alumno/student.controller.ts b/src/alumno/student.controller.ts
index 1e78037..73b7cd3 100644
--- a/src/alumno/student.controller.ts
+++ b/src/alumno/student.controller.ts
@@ -4,7 +4,7 @@ import { CreateStudentDto } from './dto/create-student.dto';
 import { Alumno } from './entities/student.entity';
 
 @Controller('student')
-export class StudentController {
+export class AlumnoController {
   constructor(private readonly alumnoService: AlumnoService) {}
 
   @Post()
@@ -22,3 +22,4 @@ export class StudentController {
     return this.alumnoService.findOne(+id);
   }
 }
+//IO
\ No newline at end of file
diff --git a/src/alumno/student.module.ts b/src/alumno/student.module.ts
index 769ecaa..ecce9ff 100644
--- a/src/alumno/student.module.ts
+++ b/src/alumno/student.module.ts
@@ -1,12 +1,14 @@
 import { Module } from '@nestjs/common';
 import { AlumnoService } from './student.service';
-import { StudentController } from './student.controller';
+import { AlumnoController } from './student.controller';
 import { TypeOrmModule } from '@nestjs/typeorm';
 import { Alumno } from './entities/student.entity';
 
 @Module({
   imports: [TypeOrmModule.forFeature([Alumno])],
-  controllers: [StudentController],
+  controllers: [AlumnoController],
   providers: [AlumnoService],
+  exports:[AlumnoService]
 })
-export class StudentModule {}
+export class AlumnoModule {}
+//IO
\ No newline at end of file
diff --git a/src/alumno/student.service.ts b/src/alumno/student.service.ts
index d531a23..5271288 100644
--- a/src/alumno/student.service.ts
+++ b/src/alumno/student.service.ts
@@ -50,3 +50,4 @@ export class AlumnoService {
       .execute();
   }
 }
+//IO
\ No newline at end of file
diff --git a/src/alumno_sancion/alumno_sancion.controller.ts b/src/alumno_sancion/alumno_sancion.controller.ts
index 41b91cf..3589235 100644
--- a/src/alumno_sancion/alumno_sancion.controller.ts
+++ b/src/alumno_sancion/alumno_sancion.controller.ts
@@ -1,16 +1,13 @@
 import { Body, Controller, Get, Param, Post } from '@nestjs/common';
 import { AlumnoSancionService } from './alumno_sancion.service';
 import { CreateAlumnoSancionDto } from './dto/create-alumno_sancion.dto';
-import { AlumnoSancion } from './entities/alumno_sancion.entity';
 
 @Controller('alumno-sancion')
 export class AlumnoSancionController {
   constructor(private readonly alumnoSancionService: AlumnoSancionService) {}
 
   @Post()
-  async create(
-    @Body() createAlumnoSancionDto: CreateAlumnoSancionDto,
-  ): Promise<AlumnoSancion> {
+  async create(@Body() createAlumnoSancionDto: CreateAlumnoSancionDto) {
     return this.alumnoSancionService.create(createAlumnoSancionDto);
   }
 
@@ -24,3 +21,4 @@ export class AlumnoSancionController {
     return this.alumnoSancionService.findOne(+id);
   }
 }
+//IO
\ No newline at end of file
diff --git a/src/alumno_sancion/alumno_sancion.module.ts b/src/alumno_sancion/alumno_sancion.module.ts
index 56789a1..9059330 100644
--- a/src/alumno_sancion/alumno_sancion.module.ts
+++ b/src/alumno_sancion/alumno_sancion.module.ts
@@ -5,10 +5,18 @@ import { TypeOrmModule } from '@nestjs/typeorm';
 import { AlumnoSancion } from './entities/alumno_sancion.entity';
 import { Alumno } from 'src/alumno/entities/student.entity';
 import { Sancion } from 'src/sancion/entities/sancion.entity';
+import { AlumnoModule } from 'src/alumno/student.module';
+import { SancionModule } from 'src/sancion/sancion.module';
+import { AlumnoService } from 'src/alumno/student.service';
 
 @Module({
-  imports:[TypeOrmModule.forFeature([AlumnoSancion,Alumno,Sancion])],
+  imports: [
+    TypeOrmModule.forFeature([AlumnoSancion, Alumno, Sancion]),
+    AlumnoModule,
+    SancionModule,
+  ],
   controllers: [AlumnoSancionController],
   providers: [AlumnoSancionService],
 })
 export class AlumnoSancionModule {}
+//IO
diff --git a/src/alumno_sancion/alumno_sancion.service.ts b/src/alumno_sancion/alumno_sancion.service.ts
index 19cce71..f3152e6 100644
--- a/src/alumno_sancion/alumno_sancion.service.ts
+++ b/src/alumno_sancion/alumno_sancion.service.ts
@@ -3,25 +3,35 @@ import { InjectRepository } from '@nestjs/typeorm';
 import { AlumnoSancion } from './entities/alumno_sancion.entity';
 import { Repository } from 'typeorm';
 import { CreateAlumnoSancionDto } from './dto/create-alumno_sancion.dto';
-import { Sancion } from 'src/sancion/entities/sancion.entity';
 import { AlumnoService } from 'src/alumno/student.service';
+import { SancionService } from 'src/sancion/sancion.service';
 
 @Injectable()
 export class AlumnoSancionService {
   constructor(
     @InjectRepository(AlumnoSancion)
     private readonly alumnosancionRepository: Repository<AlumnoSancion>,
+
+    private readonly alumnoService: AlumnoService,
+    private readonly sancionService: SancionService,
   ) {}
 
   async create(
     createAlumnoSancionDto: CreateAlumnoSancionDto,
-  ): Promise<AlumnoSancion> {
+  ) {
     const { id_sancion, id_cuenta } = createAlumnoSancionDto;
 
-    //   Crear la entidad con relaciones
+    const alumno = await this.alumnoService.findOne(id_cuenta);
+    const sancion = await this.sancionService.findOne(id_sancion);
+
+    if (!alumno)
+      throw new NotFoundException(`Alumno ${id_cuenta} no encontrado`);
+    if (!sancion)
+      throw new NotFoundException(`Sancion ${id_sancion} no encontrada`);
+
     const alumnosancion = this.alumnosancionRepository.create({
-      id_sancion: { id_sancion }, // se asigna por FK
-      id_cuenta: { id_cuenta }, // se asigna por FK
+      alumno,
+      sancion,
     });
 
     return await this.alumnosancionRepository.save(alumnosancion);
@@ -33,7 +43,7 @@ export class AlumnoSancionService {
 
   async findOne(id_cuenta: number): Promise<AlumnoSancion> {
     const alusancion = await this.alumnosancionRepository.findOne({
-      where: { id_cuenta: { id_cuenta } },
+      where: { alumno: { id_cuenta } },
     });
     if (!alusancion) {
       throw new NotFoundException(`Student with ID ${id_cuenta} not found`);
@@ -41,3 +51,4 @@ export class AlumnoSancionService {
     return alusancion;
   }
 }
+//IO
\ No newline at end of file
diff --git a/src/alumno_sancion/entities/alumno_sancion.entity.ts b/src/alumno_sancion/entities/alumno_sancion.entity.ts
index 7aef074..b1da1dc 100644
--- a/src/alumno_sancion/entities/alumno_sancion.entity.ts
+++ b/src/alumno_sancion/entities/alumno_sancion.entity.ts
@@ -23,15 +23,15 @@ export class AlumnoSancion {
 
   @ManyToOne(() => Alumno, (student) => student.sanciones, {
     eager: true,
-    nullable: true,
+    nullable: false,
   })
   @JoinColumn({ name: 'id_cuenta' })
-  id_cuenta: Alumno;
+  alumno: Alumno;
 
   @ManyToOne(() => Sancion, (sancion) => sancion.sancion, {
     eager: true,
-    nullable: true,
+    nullable: false,
   })
   @JoinColumn({ name: 'id_sancion' })
-  id_sancion: Sancion;
+  sancion: Sancion;
 }
diff --git a/src/app.module.ts b/src/app.module.ts
index 5f6aa50..69bc42a 100644
--- a/src/app.module.ts
+++ b/src/app.module.ts
@@ -3,7 +3,7 @@ import { ConfigModule, ConfigService } from '@nestjs/config';
 import { AppController } from './app.controller';
 import { AppService } from './app.service';
 import { TypeOrmModule } from '@nestjs/typeorm';
-import { StudentModule } from './alumno/student.module';
+import { AlumnoModule } from './alumno/student.module';
 import { UserModule } from './user/user.module';
 import { Perfil, User } from './user/entities/user.entity';
 import { DetalleServicioModule } from './detalle_servicio/detalle_servicio.module';
@@ -48,11 +48,10 @@ import { Sancion } from './sancion/entities/sancion.entity';
       }),
     }),
     UserModule,
-    StudentModule,
+    AlumnoModule,
     DetalleServicioModule,
     PeriodoModule,
     ServicioModule,
-    StudentModule,
     SancionModule,
     AlumnoSancionModule,
   ],
@@ -60,3 +59,4 @@ import { Sancion } from './sancion/entities/sancion.entity';
   providers: [AppService],
 })
 export class AppModule {}
+//IO
\ No newline at end of file
diff --git a/src/sancion/entities/sancion.entity.ts b/src/sancion/entities/sancion.entity.ts
index 77b3d6e..9c90921 100644
--- a/src/sancion/entities/sancion.entity.ts
+++ b/src/sancion/entities/sancion.entity.ts
@@ -14,7 +14,7 @@ export class Sancion {
 
   @OneToMany(
     () => AlumnoSancion,
-    (alusancion) => alusancion.id_sancion,
+    (alusancion) => alusancion.sancion,
   )
   alumnosSancionados: AlumnoSancion[];
 }
diff --git a/src/sancion/sancion.module.ts b/src/sancion/sancion.module.ts
index aa8774e..51f7b05 100644
--- a/src/sancion/sancion.module.ts
+++ b/src/sancion/sancion.module.ts
@@ -1,9 +1,14 @@
 import { Module } from '@nestjs/common';
 import { SancionService } from './sancion.service';
 import { SancionController } from './sancion.controller';
+import { TypeOrmModule } from '@nestjs/typeorm';
+import { Sancion } from './entities/sancion.entity';
 
 @Module({
+  imports:[TypeOrmModule.forFeature([Sancion])],
   controllers: [SancionController],
   providers: [SancionService],
+  exports:[SancionService],
 })
 export class SancionModule {}
+//IO
\ No newline at end of file
diff --git a/src/sancion/sancion.service.ts b/src/sancion/sancion.service.ts
index d64a702..50f6e77 100644
--- a/src/sancion/sancion.service.ts
+++ b/src/sancion/sancion.service.ts
@@ -1,9 +1,16 @@
-import { Injectable } from '@nestjs/common';
+import { Injectable, NotFoundException } from '@nestjs/common';
 import { CreateSancionDto } from './dto/create-sancion.dto';
 import { UpdateSancionDto } from './dto/update-sancion.dto';
+import { Sancion } from './entities/sancion.entity';
+import { InjectRepository } from '@nestjs/typeorm';
+import { Repository } from 'typeorm';
 
 @Injectable()
 export class SancionService {
+  constructor(
+    @InjectRepository(Sancion)
+    private readonly sancionRepository: Repository<Sancion>
+  ){}
   create(createSancionDto: CreateSancionDto) {
     return 'This action adds a new sancion';
   }
@@ -12,8 +19,14 @@ export class SancionService {
     return `This action returns all sancion`;
   }
 
-  findOne(id: number) {
-    return `This action returns a #${id} sancion`;
+  async findOne(id_sancion: number): Promise<Sancion> {
+    const sancion = await this.sancionRepository.findOne({
+      where: { id_sancion },
+    });
+    if (!sancion) {
+      throw new NotFoundException(`Sancion not found`);
+    }
+    return sancion;
   }
 
   update(id: number, updateSancionDto: UpdateSancionDto) {
@@ -24,3 +37,4 @@ export class SancionService {
     return `This action removes a #${id} sancion`;
   }
 }
+//IO
\ No newline at end of file
diff --git a/src/user/user.controller.ts b/src/user/user.controller.ts
index c7f5aa2..37bab3d 100644
--- a/src/user/user.controller.ts
+++ b/src/user/user.controller.ts
@@ -17,8 +17,8 @@ export class UserController {
   constructor(private readonly userService: UserService) {}
 
   @Post()
-  async Login(@Body() data: CreateUserDto) {
-    return this.userService.Login(data);
+  async Login(@Body() data: CreateUserDto, @Res() res: Response) {
+    return this.userService.Login(data, res);
   }
 
   @UseGuards(AuthGuard('jwt'))
diff --git a/src/user/user.service.ts b/src/user/user.service.ts
index c65627c..32af2af 100644
--- a/src/user/user.service.ts
+++ b/src/user/user.service.ts
@@ -11,6 +11,7 @@ export class UserService {
   constructor(
     @InjectRepository(User)
     private userRepository: Repository<User>,
+    private jwtService: JwtService,
   ) {}
 
   async findOneByNameandPassword(data: CreateUserDto): Promise<User> {
@@ -21,14 +22,26 @@ export class UserService {
     });
 
     if (!user) {
-      throw new NotFoundException(`El usuario ${usuario} no fue encontrado`);
+      throw new NotFoundException(`El usuario o la contraseña es incorrecta`);
     }
 
     return user;
   }
 
-  async Login(data: CreateUserDto) {
+  async Login(data: CreateUserDto, res: Response) {
     const user = await this.findOneByNameandPassword(data);
-    return user;
+
+    const payload = { id: user.id_usuario, usuario: user.usuario };
+    const token = await this.jwtService.signAsync(payload);
+
+    res.cookie('token', token, {
+      httpOnly: true,
+      secure: process.env.NODE_ENV === 'production', // en dev desactívalo
+      sameSite: 'strict',
+      path: '/',
+    });
+
+    return res.json({ message: 'Inicio de sesión exitoso' });
   }
 }
+//IO
\ No newline at end of file